The first report on last month’s Jeju Air crash in South Korea has confirmed traces of bird strikes in the plane’s engines, though officials haven’t determined the cause of the accident that killed all but two of the 181 people on board.

Authorities have suggested that migratory bird strikes were the cause of last month's deadly plane crash in South Korea, according to multiple reports.

The exact cause of the Jeju Air crash remains unclear, and the investigation is complicated because the black boxes stopped recording four minutes before impact.