PARIS – The co-pilot of Germanwings Flight 4525 tried a controlled descent on the previous flight that morning to Barcelona before the plane crashed into a mountainside in March on its way back to Germany, French air accident investigators said in a new report released Wednesday.

Co-pilot Andreas Lubitz repeatedly set the plane into a descent, then brought it back up again on a flight on the same A320 jet from Duesseldorf to Barcelona, the BEA investigation agency said in the report.

The report said the pilot appeared to have left the cockpit during that flight as well.

Cockpit data shows that Lubitz put the plane into descent mode five times in a four and half-minute period during the Duesseldorf-Barcelona leg.

The report is only an interim report. The BEA said it is continuing to look at the “systemic failings that may have led to this accident or similar events.”

The investigators said their main focus is on “the current balance between medical confidentiality and flight safety” and the “compromises” made on security after the Sept. 11 attacks in the U.S., notably on cockpit door locking systems.

Prosecutors have previously said Lubitz intentionally crashed the plane on its return flight from Barcelona to Duesseldorf in the French Alps on March 24, killing all 150 on board.

Lufthansa spokesman Helmut Tolksdorf said by phone from Frankfurt that the airline had not yet had time to analyze the new details released by French authorities and planned no immediate comment.

Lufthansa is the parent company of Germanwings.