A dozen planes filed with Russian peacekeepers headed for Nagorno-Karabakh on Tuesday, hours after Armenia and Azerbaijan agreed to halt fighting over the separatist region and amid signs this cease-fire would hold where others hadn't.

The truce came after significant advances by Azerbaijani forces that the Nagorno-Karabakh leader said made it impossible for their side to carry on — but angered many Armenians, who stormed government buildings overnight, demanding the Parliament invalidate the agreement. Dozens of protesters gathered again Tuesday morning in front of the parliament building in the Armenian capital of Yerevan.

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Azerbaijanis celebrate with national flags in Baku, Azerbaijan, Tuesday, Nov. 10, 2020. Armenia and Azerbaijan announced an agreement early Tuesday to halt fighting over the Nagorno-Karabakh region of Azerbaijan under a pact signed with Russia that calls for deployment of nearly 2,000 Russian peacekeepers and territorial concessions. (AP Photo)

A dozen planes filed with Russian peacekeepers headed for Nagorno-Karabakh on Tuesday, hours after Armenia and Azerbaijan agreed to halt fighting over the separatist region and amid signs this cease-fire would hold where others hadn't.
Azerbaijanis celebrate waving national and Turkish flags in Baku, Azerbaijan, Tuesday, Nov. 10, 2020. Armenia and Azerbaijan announced an agreement early Tuesday to halt fighting over the Nagorno-Karabakh region of Azerbaijan under a pact signed with Russia that calls for deployment of nearly 2,000 Russian peacekeepers and territorial concessions. (AP Photo)

Several cease-fires announced over the past six weeks crumbled almost immediately, but the current agreement appeared to be holding, with neither side reporting any more fighting since it came into force.
This photo made from the footage provided by Russian Defense Ministry press service on in Tuesday, Nov. 10, 2020 shows Russian peacekeepers taking on a board of military plane in unknown place in Russia. Scores of Russian peacekeepers were heading to Nagorno-Karabakh on Tuesday morning, hours after Armenia and Azerbaijan agreed to halt the fighting over the separatist region in a pact signed with Moscow which envisions the deployment of nearly 2,000 Russian peacekeepers and territorial concessions. (Russian Defense Ministry Press Service via AP)

But on Tuesday he explained that he was left with no choice, saying the army had told him it was necessary.
A woman wheels a stroller with a child as police officers guard in front of the government building in Yerevan, Armenia, Tuesday, Nov. 10, 2020. Some thousands of people streamed to the main square in the Armenian capital early Tuesday to protest the agreement to halt fighting over the Nagorno-Karabakh region, many shouting "We won't give up our land." Some of them broke into the main government building, saying they were searching for Pashinian, who apparently had already departed. (AP PhotoDmitri Lovetsky)

Azerbaijani President Ilham Aliyev referred to the agreement as a “glorious victory” on Twitter, and Azerbaijanis flooded their capital city to celebrate.
Police officers guard in front of the government building in Yerevan, Armenia, Tuesday, Nov. 10, 2020. Thousands of people streamed to the main square in the Armenian capital early Tuesday to protest the agreement to halt fighting over the Nagorno-Karabakh region, many shouting "We won't give up our land." Some of them broke into the main government building, saying they were searching for Pashinian, who apparently had already departed. (AP PhotoDmitri Lovetsky)

The agreement also calls for transport links to be established through Armenia linking Azerbaijan and its western exclave of Nakhchivan, which is surrounded by Armenia, Iran and Turkey.
People argue as the police officers guard in front of the government building in Yerevan, Armenia, Tuesday, Nov. 10, 2020. Thousands of people streamed to the main square in the Armenian capital early Tuesday to protest the agreement to halt fighting over the Nagorno-Karabakh region, many shouting "We won't give up our land." Some of them broke into the main government building, saying they were searching for Pashinian, who apparently had already departed. (AP PhotoDmitri Lovetsky)

People argue as the police officers guard in front of the government building in Yerevan, Armenia, Tuesday, Nov. 10, 2020. Thousands of people streamed to the main square in the Armenian capital early Tuesday to protest the agreement to halt fighting over the Nagorno-Karabakh region, many shouting "We won't give up our land." Some of them broke into the main government building, saying they were searching for Pashinian, who apparently had already departed. (AP PhotoDmitri Lovetsky)
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Azerbaijanis celebrate with national flags in Baku, Azerbaijan, Tuesday, Nov. 10, 2020. Armenia and Azerbaijan announced an agreement early Tuesday to halt fighting over the Nagorno-Karabakh region of Azerbaijan under a pact signed with Russia that calls for deployment of nearly 2,000 Russian peacekeepers and territorial concessions. (AP Photo)

A dozen planes filed with Russian peacekeepers headed for Nagorno-Karabakh on Tuesday, hours after Armenia and Azerbaijan agreed to halt fighting over the separatist region and amid signs this cease-fire would hold where others hadn't.

Azerbaijanis celebrate waving national and Turkish flags in Baku, Azerbaijan, Tuesday, Nov. 10, 2020. Armenia and Azerbaijan announced an agreement early Tuesday to halt fighting over the Nagorno-Karabakh region of Azerbaijan under a pact signed with Russia that calls for deployment of nearly 2,000 Russian peacekeepers and territorial concessions. (AP Photo)

Several cease-fires announced over the past six weeks crumbled almost immediately, but the current agreement appeared to be holding, with neither side reporting any more fighting since it came into force.

This photo made from the footage provided by Russian Defense Ministry press service on in Tuesday, Nov. 10, 2020 shows Russian peacekeepers taking on a board of military plane in unknown place in Russia. Scores of Russian peacekeepers were heading to Nagorno-Karabakh on Tuesday morning, hours after Armenia and Azerbaijan agreed to halt the fighting over the separatist region in a pact signed with Moscow which envisions the deployment of nearly 2,000 Russian peacekeepers and territorial concessions. (Russian Defense Ministry Press Service via AP)

But on Tuesday he explained that he was left with no choice, saying the army had told him it was necessary.

A woman wheels a stroller with a child as police officers guard in front of the government building in Yerevan, Armenia, Tuesday, Nov. 10, 2020. Some thousands of people streamed to the main square in the Armenian capital early Tuesday to protest the agreement to halt fighting over the Nagorno-Karabakh region, many shouting "We won't give up our land." Some of them broke into the main government building, saying they were searching for Pashinian, who apparently had already departed. (AP PhotoDmitri Lovetsky)

Azerbaijani President Ilham Aliyev referred to the agreement as a “glorious victory” on Twitter, and Azerbaijanis flooded their capital city to celebrate.

Police officers guard in front of the government building in Yerevan, Armenia, Tuesday, Nov. 10, 2020. Thousands of people streamed to the main square in the Armenian capital early Tuesday to protest the agreement to halt fighting over the Nagorno-Karabakh region, many shouting "We won't give up our land." Some of them broke into the main government building, saying they were searching for Pashinian, who apparently had already departed. (AP PhotoDmitri Lovetsky)

The agreement also calls for transport links to be established through Armenia linking Azerbaijan and its western exclave of Nakhchivan, which is surrounded by Armenia, Iran and Turkey.

People argue as the police officers guard in front of the government building in Yerevan, Armenia, Tuesday, Nov. 10, 2020. Thousands of people streamed to the main square in the Armenian capital early Tuesday to protest the agreement to halt fighting over the Nagorno-Karabakh region, many shouting "We won't give up our land." Some of them broke into the main government building, saying they were searching for Pashinian, who apparently had already departed. (AP PhotoDmitri Lovetsky)

People argue as the police officers guard in front of the government building in Yerevan, Armenia, Tuesday, Nov. 10, 2020. Thousands of people streamed to the main square in the Armenian capital early Tuesday to protest the agreement to halt fighting over the Nagorno-Karabakh region, many shouting "We won't give up our land." Some of them broke into the main government building, saying they were searching for Pashinian, who apparently had already departed. (AP PhotoDmitri Lovetsky)

Armenia and Azerbaijan have been locked in a conflict over Nagorno-Karabakh for decades. The region lies within Azerbaijan but has been under control of ethnic Armenian forces backed by Armenia since a separatist war there ended in 1994. Heavy fighting erupted in late September — the biggest escalation of the conflict in a quarter-century — and has left hundreds, possibly thousands, dead.

Azerbaijanis celebrate with national flags in Baku, Azerbaijan, Tuesday, Nov. 10, 2020. Armenia and Azerbaijan announced an agreement early Tuesday to halt fighting over the Nagorno-Karabakh region of Azerbaijan under a pact signed with Russia that calls for deployment of nearly 2,000 Russian peacekeepers and territorial concessions. (AP Photo)

Azerbaijanis celebrate with national flags in Baku, Azerbaijan, Tuesday, Nov. 10, 2020. Armenia and Azerbaijan announced an agreement early Tuesday to halt fighting over the Nagorno-Karabakh region of Azerbaijan under a pact signed with Russia that calls for deployment of nearly 2,000 Russian peacekeepers and territorial concessions. (AP Photo)

Several cease-fires announced over the past six weeks crumbled almost immediately, but the current agreement appeared to be holding, with neither side reporting any more fighting since it came into force.

It came days after Azerbaijan pressed its offensive deeper into the region and took control of the city of Shushi, which is strategically positioned on heights overlooking the regional capital of Stepanakert.

Armenian Prime Minister Nikol Pashinian said on Facebook that calling an end to the fight was “extremely painful for me personally and for our people."

Azerbaijanis celebrate waving national and Turkish flags in Baku, Azerbaijan, Tuesday, Nov. 10, 2020. Armenia and Azerbaijan announced an agreement early Tuesday to halt fighting over the Nagorno-Karabakh region of Azerbaijan under a pact signed with Russia that calls for deployment of nearly 2,000 Russian peacekeepers and territorial concessions. (AP Photo)

Azerbaijanis celebrate waving national and Turkish flags in Baku, Azerbaijan, Tuesday, Nov. 10, 2020. Armenia and Azerbaijan announced an agreement early Tuesday to halt fighting over the Nagorno-Karabakh region of Azerbaijan under a pact signed with Russia that calls for deployment of nearly 2,000 Russian peacekeepers and territorial concessions. (AP Photo)

But on Tuesday he explained that he was left with no choice, saying the army had told him it was necessary.

“We found ourselves in a situation when there was no alternative to signing the agreement,” Pashinian was quoted by Russia's Interfax news agency as saying.

Nagorno-Karabakh’s separatist leader Arayik Harutyunyan echoed Pashinian’s sentiment. He said: "Had the hostilities continued at the same pace, we would have lost all of Artsakh (an Armenian name for Nagorno-Karabakh) within days.”

This photo made from the footage provided by Russian Defense Ministry press service on in Tuesday, Nov. 10, 2020 shows Russian peacekeepers taking on a board of military plane in unknown place in Russia. Scores of Russian peacekeepers were heading to Nagorno-Karabakh on Tuesday morning, hours after Armenia and Azerbaijan agreed to halt the fighting over the separatist region in a pact signed with Moscow which envisions the deployment of nearly 2,000 Russian peacekeepers and territorial concessions. (Russian Defense Ministry Press Service via AP)

This photo made from the footage provided by Russian Defense Ministry press service on in Tuesday, Nov. 10, 2020 shows Russian peacekeepers taking on a board of military plane in unknown place in Russia. Scores of Russian peacekeepers were heading to Nagorno-Karabakh on Tuesday morning, hours after Armenia and Azerbaijan agreed to halt the fighting over the separatist region in a pact signed with Moscow which envisions the deployment of nearly 2,000 Russian peacekeepers and territorial concessions. (Russian Defense Ministry Press Service via AP)

Azerbaijani President Ilham Aliyev referred to the agreement as a “glorious victory” on Twitter, and Azerbaijanis flooded their capital city to celebrate.

Russia’s Defense Ministry said that 12 planes carrying peacekeepers and military equipment departed for the region Tuesday. A total of 1,960 Russian peacekeepers are to be deployed in Nagorno-Karabakh under a five-year mandate.

The pact calls for Armenian forces to turn over control of some areas it held outside the borders of Nagorno-Karabakh, including the Lachin region, where the main road leading from Nagorno-Karabakh to Armenia passes through. The agreement calls for the road, the so-called Lachin Corridor, to remain open and be protected by Russian peacekeepers.

A woman wheels a stroller with a child as police officers guard in front of the government building in Yerevan, Armenia, Tuesday, Nov. 10, 2020. Some thousands of people streamed to the main square in the Armenian capital early Tuesday to protest the agreement to halt fighting over the Nagorno-Karabakh region, many shouting "We won't give up our land." Some of them broke into the main government building, saying they were searching for Pashinian, who apparently had already departed. (AP PhotoDmitri Lovetsky)

A woman wheels a stroller with a child as police officers guard in front of the government building in Yerevan, Armenia, Tuesday, Nov. 10, 2020. Some thousands of people streamed to the main square in the Armenian capital early Tuesday to protest the agreement to halt fighting over the Nagorno-Karabakh region, many shouting "We won't give up our land." Some of them broke into the main government building, saying they were searching for Pashinian, who apparently had already departed. (AP PhotoDmitri Lovetsky)

The agreement also calls for transport links to be established through Armenia linking Azerbaijan and its western exclave of Nakhchivan, which is surrounded by Armenia, Iran and Turkey.

Nagorno-Karabakh military have reported over 1,200 troops killed in the six weeks of fighting. Azerbaijan hasn't disclosed its military losses. Scores of civilians have also been killed and wounded on both sides.

Police officers guard in front of the government building in Yerevan, Armenia, Tuesday, Nov. 10, 2020. Thousands of people streamed to the main square in the Armenian capital early Tuesday to protest the agreement to halt fighting over the Nagorno-Karabakh region, many shouting "We won't give up our land." Some of them broke into the main government building, saying they were searching for Pashinian, who apparently had already departed. (AP PhotoDmitri Lovetsky)

Police officers guard in front of the government building in Yerevan, Armenia, Tuesday, Nov. 10, 2020. Thousands of people streamed to the main square in the Armenian capital early Tuesday to protest the agreement to halt fighting over the Nagorno-Karabakh region, many shouting "We won't give up our land." Some of them broke into the main government building, saying they were searching for Pashinian, who apparently had already departed. (AP PhotoDmitri Lovetsky)

 People argue as the police officers guard in front of the government building in Yerevan, Armenia, Tuesday, Nov. 10, 2020. Thousands of people streamed to the main square in the Armenian capital early Tuesday to protest the agreement to halt fighting over the Nagorno-Karabakh region, many shouting "We won't give up our land." Some of them broke into the main government building, saying they were searching for Pashinian, who apparently had already departed. (AP PhotoDmitri Lovetsky)

People argue as the police officers guard in front of the government building in Yerevan, Armenia, Tuesday, Nov. 10, 2020. Thousands of people streamed to the main square in the Armenian capital early Tuesday to protest the agreement to halt fighting over the Nagorno-Karabakh region, many shouting "We won't give up our land." Some of them broke into the main government building, saying they were searching for Pashinian, who apparently had already departed. (AP PhotoDmitri Lovetsky)