Veteran Saudi journalist Jamal Khashoggi disappeared almost two weeks ago while on a visit to the Saudi Consulate in Istanbul, sparking an international uproar involving the kingdom, Turkey and the United States that remains unresolved.

Khashoggi, a Washington Post contributor, had written columns critical of Saudi Crown Prince Mohammed bin Salman, the kingdom's stalemated war in Yemen and its crackdown on activists and businessmen.

Turkish officials say they fear a team of Saudi agents killed and dismembered Khashoggi, and they have released surveillance footage of the alleged perpetrators and mysterious movements outside the consulate on Oct. 2, the day he entered. The kingdom says the allegations are "baseless" but has offered no evidence Khashoggi ever left the consulate.

A security guard waits to enter Saudi Arabia's consulate in Istanbul, Wednesday, Oct. 10, 2018. Turkish officials have said they believe Saudi writer and government critic Jamal Khashoggi, was killed inside the consulate after he visited the mission to obtain a document required to marry his Turkish fiancee. Saudi Arabia has denied the allegations. (AP PhotoLefteris Pitarakis)

A security guard waits to enter Saudi Arabia's consulate in Istanbul, Wednesday, Oct. 10, 2018. Turkish officials have said they believe Saudi writer and government critic Jamal Khashoggi, was killed inside the consulate after he visited the mission to obtain a document required to marry his Turkish fiancee. Saudi Arabia has denied the allegations. (AP PhotoLefteris Pitarakis)

Here is a look at what we know about the disappearance.

WHO IS JAMAL KHASHOGGI?

Khashoggi is a longtime Saudi journalist, foreign correspondent, editor and columnist whose work has been controversial in the past in the ultraconservative Sunni kingdom. He went into self-imposed exile in the United States following the ascension of Prince Mohammed, now next in line to succeed his father, the 82-year-old King Salman.

Security guards stand outside the Saudi Arabia's consulate in Istanbul, Tuesday, Oct. 9, 2018. Turkey said Tuesday it will search the consulate as it investigates why journalist Jamal Khashoggi, a contributor to the Washington Post, vanished there Oct. 2, an extraordinary probe of a diplomatic post amid Turkish officials' fears the writer had been killed inside the building. Saudi officials said he left the building unharmed.(AP PhotoLefteris Pitarakis)

Security guards stand outside the Saudi Arabia's consulate in Istanbul, Tuesday, Oct. 9, 2018. Turkey said Tuesday it will search the consulate as it investigates why journalist Jamal Khashoggi, a contributor to the Washington Post, vanished there Oct. 2, an extraordinary probe of a diplomatic post amid Turkish officials' fears the writer had been killed inside the building. Saudi officials said he left the building unharmed.(AP PhotoLefteris Pitarakis)

Khashoggi was known for his interviews and travels with Osama bin Laden between 1987 and 1995, including in Afghanistan, where he wrote about the battle against the Soviet occupation. In the early 1990s, he tried to persuade bin Laden to reconcile with the Saudi royal family and return home from his base in Sudan, but the al-Qaida leader refused.

Khashoggi maintained ties with Saudi elites and was viewed as a link between the West and the often opaque royal court. As a contributor to the Post, Khashoggi has written extensively about Saudi Arabia, including criticizing its war in Yemen, its recent diplomatic spat with Canada and its arrest of women's rights activists after the lifting of a ban on women driving.

WHAT HAPPENED TO HIM?

FILE- In this April 9, 2018 file photo, Saudi Crown Prince Mohammed bin Salman is welcomed by French Prime Minister Edouard Philippe in Paris, France. The disappearance of Saudi journalist and contributor to The Washington Post Jamal Khashoggi on Oct. 2, 2018, in Turkey, peels away a carefully cultivated reformist veneer promoted about the Saudi Crown Prince, instead exposing its autocratic tendencies. The kingdom long has been known to grab rambunctious princes or opponents abroad and spirit them back to Riyadh on private planes. But the disappearance of Khashoggi, who Turkish officials fear has been killed, potentially has taken the practice to a new, macabre level by grabbing a writer who could both navigate Saudi Arabia’s byzantine royal court and explain it to the West. (AP PhotoFrancois Mori, File)

FILE- In this April 9, 2018 file photo, Saudi Crown Prince Mohammed bin Salman is welcomed by French Prime Minister Edouard Philippe in Paris, France. The disappearance of Saudi journalist and contributor to The Washington Post Jamal Khashoggi on Oct. 2, 2018, in Turkey, peels away a carefully cultivated reformist veneer promoted about the Saudi Crown Prince, instead exposing its autocratic tendencies. The kingdom long has been known to grab rambunctious princes or opponents abroad and spirit them back to Riyadh on private planes. But the disappearance of Khashoggi, who Turkish officials fear has been killed, potentially has taken the practice to a new, macabre level by grabbing a writer who could both navigate Saudi Arabia’s byzantine royal court and explain it to the West. (AP PhotoFrancois Mori, File)

Khashoggi, whose 60th birthday was on Saturday, went to the Saudi Consulate in Istanbul's upscale 4th Levent neighborhood on Sept. 28 seeking documents so he could be married to his Turkish fiancee, Hatice Cengiz. He was told to return to the consulate on Oct. 2 to pick up those documents, Cengiz says.

Surveillance footage later aired on Turkish state television shows Khashoggi walking into the consulate at 1:14 p.m. on Oct. 2. A little less than two hours later, surveillance footage shows several vehicles with diplomatic license plates move from the consulate to the consul's home some 2 kilometers (1.2 miles) away.

Cengiz, who spent hours waiting for Khashoggi outside while holding his mobile phones, says her fiance never walked out of the consulate to meet her. Surveillance footage shows her pacing around outside at 5:33 p.m., speaking on her phone. No footage made public so far has shown Khashoggi walked out of the consulate.

WHAT IS TURKEY SAYING?

Turkish officials, speaking on condition of anonymity to discuss the investigation, say they fear Saudi Arabia killed Khashoggi. They claim they have audio and video recordings of Khashoggi being interrogated, killed and dismembered. However, no such recordings have been released publicly so far.

Turkish security officials, rather than holding news conferences, have leaked information through pro-government media. Newspapers published the names and photographs of 15 Saudi men in the country's military and security services who are said to have formed an "assassination squad" sent to target Khashoggi. Turkish officials told The Associated Press one of those men was an "autopsy expert."

Turkish media have also released a series of videos, apparently taken from surveillance cameras, showing the alleged Saudi agents arriving on private jets the day Khashoggi disappeared, checking into and out of hotels near the consulate, and then flying out that night.

A Turkish newspaper also claimed that Khashoggi's Apple Watch recorded audio of his slaying and transmitted it to his iPhone outside the consulate and to his iCloud account. However, the newspaper did not explain how the alleged recording was transmitted and included a claim that Khashoggi's assailants used his finger to unlock it when such watches don't have fingerprint ID scanners.

Turkish officials have not responded to questions from the AP about Khashoggi's Apple Watch. Analysts have suggested Turkey may be trying to protect its intelligence-gathering methods by leaking information this way.

WHAT IS SAUDI ARABIA SAYING?

Saudi Arabia has offered no explanation for how the writer could have left the consulate and disappeared into Istanbul as his fiancee stood outside waiting for him.

Early Saturday, Saudi Interior Minister Prince Abdulaziz bin Saud said: "What has been circulating in terms of supposed orders to kill him are outright lies and baseless allegations against the kingdom's government."

Meanwhile, Saudi media has tried to blame the crisis on Qatar, which the kingdom and three other Arab nations now boycott as part of a bitter political dispute, without offering proof of that country's involvement. The Qatar-funded satellite network Al-Jazeera has extensively focused on Khashoggi's disappearance over the last week.

A Saudi-owned satellite news channel, meanwhile, has begun referring to the alleged 15-man team as "tourists," without providing evidence to support the claim.

WHAT IS THE U.S. SAYING?

President Donald Trump has threatened "severe punishment" if authorities determine Saudi Arabia was behind Khashoggi's disappearance. However, he also has said he wants to maintain the arms deals he struck with the kingdom on a trip to Riyadh. Meanwhile, American lawmakers are threatening to sanction individual Saudi officials if evidence links them to the writer's disappearance.

WHAT HAPPENS NEXT?

A Saudi team has arrived in Turkey to investigate Khashoggi's disappearance. Meanwhile, Turkey has said it will search the Saudi Consulate for evidence, but that has yet to happen. Turkey's Foreign Minister Mevlut Cavusoglu said Saturday that Saudi Arabia had not yet cooperated with Turkey on the search for Khashoggi. That could force Turkey's hand in leaking more information about the case to pressure the kingdom to cooperate.