Investigators found the charred and dented flight data recorder of an El Al Boeing 747 on Wednesday and said the "black box" could provide clues to why the jet slammed into a suburban apartment complex.
The briefcase-sized box was found as hundreds of searchers, sifting carefully through an unstable mountain of rubble and wreckage, pulled more bodies from the apartment building destroyed in Sunday's crash.
By Wednesday night, 40 corpses had been removed from the smoldering rubble and 250 people were still unaccounted for, according to a City Hall spokesman. He said the missing were presumed dead.
"The large number of victims of the jumbo jet disaster that cannot be identified will likely be buried in a mass grave," the Amsterdam newspaper De Telegraaf said in its Wednesday editions.
Authorities said they hoped the flight recorder would provide technical details of the last moments before the Boeing 747-200 cargo plane crashed into the 10-story building 10 miles east of Schiphol Airport, destroying 80 of its 230 apartments.
The plane's voice recorder was still missing, said Hans Scholten, a Dutch aviation agency spokesman, "which is more important for investigators."
At a news conference Wednesday, Henk Wolleswinkel, a senior inspector at the Dutch aviation authority, said only one of the plane's starboard engines had been found, not two as reported earlier.
He declined to comment on a Dutch television report quoting a Schiphol Airport official as saying the same El Al jumbo jet had landed at the airport in July with one engine on fire.
Wolleswinkel said the outer starboard engine was found Monday and showed no signs of fire. "At this moment there are no positive indications there was something wrong with the engine," he said.
Wolleswinkel said there was an "intensive migration of birds" in the area the night the El Al jetliner went down, but there was no indication the birds were sucked into the turbines, causing the crash.
The Israeli airline, meanwhile, said it was setting up an emergency fund for survivors of crash victims.