Oct. 31 (UPI) -- After three days of searching, investigators looking for Lion Air Flight 610 said they heard "pings" Wednesday that could lead them to the plane's wreckage off the Indonesian coast.
The pings likely came from a locator beacon in the plane's "black boxes," which would help investigators narrow the search for the downed jetliner.
"Based on the presentation of the head of the National Search and Rescue Agency, the coordinates of the suspected body of the aircraft have been found," Hadi Tjahjanto told an Indonesian TV station.
Flight JT610 crashed Monday moments after take-off, carrying 189 passengers and crew. All are presumed dead.
Recovery crews have found debris, human remains and personal belongings, but no airplane. Authorities said 48 bodies have been recovered so far. Family members are providing DNA samples to confirm identities and Indonesian President Joko Widodo helped crews sort and log each piece of wreckage.
Wednesday, Lion Air fired its technical director on instructions from the Indonesian government. Transportation officials are also considering sanctions for Lion Air, a discount carrier.
Flight 610, a new Boeing 737 MAX 8, had only been in service for a few months.
Authorities are checking the plane's maintenance history, and found that flight crews reported a problem with the plane the night before the crash. A repair was made and the plane was cleared to fly, Lion Air's CEO said.
The flight left Jakarta early Monday but pilots immediately requested a return to the airport after a problem with altitude. Radar data show the plane did not make the turn toward the airport before it crashed, and the pilots didn't declare an official emergency.
Former Federal Aviation Administration inspector David Soucie said that fact is concerning.
"They just said, 'We're going back,'" Soucie told CNN. "The aircraft made a very steep dive after that, which is not typical of what they would have done. They would have maintained altitude and made that turn and come back."