JAKARTA, Indonesia (AP) — New details about the crashed Lion Air's jet previous flight cast doubt on the Indonesian airline's claim to have fixed technical problems.

The plane plunged into the Java Sea early Monday, just minutes after taking off, killing all 189 people on board.

Herson, head of Bali-Nusa Tenggara Airport Authority, says the pilot on the Boeing 737 MAX 8's previous flight on Sunday requested to return to the airport not long after takeoff but then reported the problem was resolved.

The fatal flight's pilots also made a "return to base" request minutes before the crash.

Investigators displayed one of the jet's flight recorders at a news conference Thursday evening and said they would immediately attempt to upload information and begin analysis.