Germanwings co-pilot Andreas Lubitz repeatedly accelerated the plane’s descent using the autopilot function when Flight 9525 was heading down toward the Alps, the French air accident investigation agency BEA said in a statement on Friday. The agency said it received the latest information from initial readings of the plane’s black box data, the Associated Press reported, citing the statement in French.

Investigators said that Lubitz used the autopilot feature to descend the plane and kept adjusting the controls to speed up the plane’s fall. They reiterated that the initial readings also indicated that Lubitz, who had locked his fellow pilot out of the cockpit, intentionally crashed the plane.

According to the statement, the flight data recorder reached the agency on Thursday evening and the teams started their investigation immediately.

The plane was headed toward Düsseldorf, Germany, from Barcelona, Spain, with 150 people on board, when it crashed into the French Alps. Workers, trying to collect debris from the crash, have so far found body parts of all the people on board, but not all of them have been traced back to the crash victims.

The first black box from the plane was found last week, while reports on Thursday said that a second black box was also found from the site of the wreckage.

Earlier reports had said that the black box recorded Lubitz’s breathing while screams of the passengers could be heard. The captain of the plane, Patrick Sondenheimer, had also yelled “open the goddamn door” from outside the locked cockpit.

Lubitz is suspected to have been suicidal at the time of the crash and a Thursday report said that he saw at least five doctors before the crash in order to avoid giving up on his pilot's license due to medical issues. Reports also suggested that Lubitz lied to doctors, saying he was taking sick leave, rather than flying planes.