SEYNE-LES-ALPES, France - The arduous search for the 150 victims of the worst aviation disaster on French soil in decades was set to resume at dawn Wednesday, as European leaders visit the site of the tragedy to pay their respects.
Germanwings budget flight 4U9525, carrying 144 passengers including 16 German teenagers returning home from a school trip, plunged for eight minutes before hitting the side of a mountain in the French Alps Tuesday with no survivors.
There was no response to desperate attempts by air traffic controllers to hail the pilots.
The accident's cause remains a mystery but authorities have recovered a black box from the Airbus A320 at the crash site, where debris was believed to be scattered over four acres of remote and inaccessible mountainous terrain, hampering rescue efforts.
More than 300 policemen and 380 firefighters have been mobilised. Lieutenant Colonel Jean-Marc Menichini said a squad of 30 mountain rescue police would resume attempts to reach the crash site by helicopter at dawn Wednesday, while a further 65 police were seeking access on foot. Five investigators had spent the night at the site.
It would take "at least a week" to search the remote site, he said, and "at least several days" to repatriate the bodies.
Video images from a government helicopter Tuesday showed a desolate snow-flecked moonscape, with steep ravines covered in scree. Debris was strewn across the mountainside, pieces of twisted metal smashed into tiny bits.
The plane was "totally destroyed", a local MP who flew over the site said, describing the scene as "horrendous".
"The biggest body parts we identified are not bigger than a briefcase," one investigator said.
A crisis cell has been set up in the area between Barcelonnette and Digne-les-Bains along with an emergency flight control centre to coordinate chopper flights to the crash site.
French President Francois Hollande, his German counterpart Angela Merkel and Spanish Prime Minister Mariano Rajoy were expected to reach the scene around 2:00 pm (1300 GMT).
The 144 passengers were mainly German and Spanish.
The high school in the small German town of Haltern attended by the 16 students on the plane was set to hold an event Wednesday to honour the victims.
"This is certainly the darkest day in the history of our city," said a tearful Bodo Klimpel, the town's mayor, Tuesday. "It is the worst thing you can imagine."
Spain, meanwhile, declared three days of mourning and was to hold a minute of silence across the country at noon Wednesday.
Opera singers Oleg Bryjak, 54, and Maria Radner, 33, were also on board, flying to their home city of Duesseldorf. Radner was travelling with her husband and baby, one of two infants on board the plane.