PARIS (AP) — First, the plane disappeared from radar screens somewhere over the French Alps, on March 24, 2015.
Then, families of the 150 people aboard Germanwings Flight 9525 started showing up at airports. In Barcelona, Spain, where loved ones had boarded the plane, and Duesseldorf, Germany, where loved ones were meant to land.
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FILE - German Chancellor Angela Merkel, left, French President Francois Hollande, right, and Spanish Prime Minister Mariano Rajoy pay respect to the victims in front of the mountain where a Germanwings jetliner crashed on Tuesday, in Le Vernet, France, Wednesday, March 25, 2015. (AP Photo/Christophe Ena, Pool, File)
FILE - In this photo taken on March 31, 2015 and provided by the French Interior Ministry, French emergency rescue services work among the debris of the Germanwings passenger jet at the crash site near Seyne-les-Alpes, France. (Yves Malenfer/Ministere de l'Interieur, File)
FILE - A convoy of hearses drive along the highway in Duisburg, Germany, June 10, 2015, taking home 16 school children who died in the Germanwings plane crash over the French Alps. (AP Photo/Martin Meissner, file)
FILE - People wait to start a minute of silence for the victims of the Germanwings plane that crashed in the French Alps, in front of the council building in Llinars del Valles, near Barcelona, Spain, March 25, 2015. (AP Photo/Emilio Morenatti, File)
FILE - Families of the Germanwings victims pay homage in Le Vernet, French Alps, July 24, 2015. (AP Photo/Claude Paris, File)
FILE - A man pays his respect to the Germanwings victims in Le Vernet, in the French Alps, Sept. 24, 2015. (AP Photo/Lionel Cironneau, File)
FILE - Friends of the German students from the crashed plane attend a mass in Llinars del Valles, near Barcelona, Spain, March 24, 2015. (AP Photo/Emilio Morenatti, File)
FILE - This photo provided by the French Interior Ministry shows French emergency rescue services work among the debris of the Germanwings passenger jet at the crash site near Seyne-les-Alpes, France, April 3, 2015. (Yves Malenfer/Ministere de l'Interieur via AP, File)
FILE - Families of the victims look at the Germanwings plane crash site one year after the crash, Thursday, March 24, 2016 in Le Vernet, France. (AP Photo/Christophe Ena, File)
FILE - A rescue worker climbs past debris at the plane crash site near Seyne-les-Alpes, France after a Germanwings jetliner crashed in the French Alps, March 25, 2015 (AP Photo/Laurent Cipriani, File)
FILE - A school girl lights a candle in front of the Joseph-Koenig Gymnasium in Haltern, western Germany, March 24, 2015, after a Germanwings plane from Barcelona crashed on its way to Duesseldorf over the French alps. (AP Photo/Martin Meissner, File)
FILE - This photo provided by the French Interior Ministry shows French emergency rescue services work among the debris of the Germanwings passenger jet at the crash site near Seyne-les-Alpes, France, March 31, 2015. (Yves Malenfer/Ministere de l'Interieur via AP, File)
FILE - Rescuers work on debris of the Germanwings jet at the crash site near Seyne-les-Alpes, France, on March 26, 2015. (AP Photo/Laurent Cipriani, File)
FILE - A student who knew some of the German students involved in a crashed plane, reacts during a minute of silence in front of the council building in Llinars del Valles, near Barcelona, Spain, March 25, 2015. (AP Photo/Emilio Morenatti, File)
FILE - Rescue workers work at the crash site after a Germanwings plane crashed over the French Alps near Seyne-les-Alpes, France, Monday, March 30, 2015. (AP Photo/Claude Paris, Pool, File)
FILE - The arrivals board shows flight 4U 9525 without a status at the airport in Duesseldorf, Germany, March 24, 2015, after a Germanwings passenger jet carrying 148 people crashed in the French Alps region. (AP Photo/Frank Augstein, File)
FILE - A rescue worker is lifted into an helicopter at the crash site after a Germanwings plane crashed over the French Alps, near Seyne-les-Alpes, France, March 26, 2015. (AP Photo/Laurent Cipriani, File)
Airport screens showed a blank spot where the flight's arrival time should have appeared.
Soon, search teams fanned out over treacherous mountainsides, rappelling off helicopters or scaling barren slopes.
At last, the first signs of debris appeared. Then, human remains.
Eventually, the plane's black boxes were found, allowing investigators to piece together the plane's final moments.
It was no accident. French and German investigators concluded that co-pilot Andreas Lubitz locked the pilot out of the cockpit, and intentionally crashed.
Local hamlets welcomed search teams and families as they waited, worried and began to grieve. Today, the village of Le Vernet hosts a monument honoring the dead, rising above a meadow overlooking Alpine peaks.
On Monday, Le Vernet will host families for a memorial ceremony and a moment of silence at 10:41 a.m., exactly 10 years after the crash.
FILE - German Chancellor Angela Merkel, left, French President Francois Hollande, right, and Spanish Prime Minister Mariano Rajoy pay respect to the victims in front of the mountain where a Germanwings jetliner crashed on Tuesday, in Le Vernet, France, Wednesday, March 25, 2015. (AP Photo/Christophe Ena, Pool, File)
FILE - In this photo taken on March 31, 2015 and provided by the French Interior Ministry, French emergency rescue services work among the debris of the Germanwings passenger jet at the crash site near Seyne-les-Alpes, France. (Yves Malenfer/Ministere de l'Interieur, File)
FILE - A convoy of hearses drive along the highway in Duisburg, Germany, June 10, 2015, taking home 16 school children who died in the Germanwings plane crash over the French Alps. (AP Photo/Martin Meissner, file)
FILE - People wait to start a minute of silence for the victims of the Germanwings plane that crashed in the French Alps, in front of the council building in Llinars del Valles, near Barcelona, Spain, March 25, 2015. (AP Photo/Emilio Morenatti, File)
FILE - Families of the Germanwings victims pay homage in Le Vernet, French Alps, July 24, 2015. (AP Photo/Claude Paris, File)
FILE - A man pays his respect to the Germanwings victims in Le Vernet, in the French Alps, Sept. 24, 2015. (AP Photo/Lionel Cironneau, File)
FILE - Friends of the German students from the crashed plane attend a mass in Llinars del Valles, near Barcelona, Spain, March 24, 2015. (AP Photo/Emilio Morenatti, File)
FILE - This photo provided by the French Interior Ministry shows French emergency rescue services work among the debris of the Germanwings passenger jet at the crash site near Seyne-les-Alpes, France, April 3, 2015. (Yves Malenfer/Ministere de l'Interieur via AP, File)
FILE - Families of the victims look at the Germanwings plane crash site one year after the crash, Thursday, March 24, 2016 in Le Vernet, France. (AP Photo/Christophe Ena, File)
FILE - A rescue worker climbs past debris at the plane crash site near Seyne-les-Alpes, France after a Germanwings jetliner crashed in the French Alps, March 25, 2015 (AP Photo/Laurent Cipriani, File)
FILE - A school girl lights a candle in front of the Joseph-Koenig Gymnasium in Haltern, western Germany, March 24, 2015, after a Germanwings plane from Barcelona crashed on its way to Duesseldorf over the French alps. (AP Photo/Martin Meissner, File)
FILE - This photo provided by the French Interior Ministry shows French emergency rescue services work among the debris of the Germanwings passenger jet at the crash site near Seyne-les-Alpes, France, March 31, 2015. (Yves Malenfer/Ministere de l'Interieur via AP, File)
FILE - Rescuers work on debris of the Germanwings jet at the crash site near Seyne-les-Alpes, France, on March 26, 2015. (AP Photo/Laurent Cipriani, File)
FILE - A student who knew some of the German students involved in a crashed plane, reacts during a minute of silence in front of the council building in Llinars del Valles, near Barcelona, Spain, March 25, 2015. (AP Photo/Emilio Morenatti, File)
FILE - Rescue workers work at the crash site after a Germanwings plane crashed over the French Alps near Seyne-les-Alpes, France, Monday, March 30, 2015. (AP Photo/Claude Paris, Pool, File)
FILE - The arrivals board shows flight 4U 9525 without a status at the airport in Duesseldorf, Germany, March 24, 2015, after a Germanwings passenger jet carrying 148 people crashed in the French Alps region. (AP Photo/Frank Augstein, File)
FILE - A rescue worker is lifted into an helicopter at the crash site after a Germanwings plane crashed over the French Alps, near Seyne-les-Alpes, France, March 26, 2015. (AP Photo/Laurent Cipriani, File)
