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.

Investigators probing the Jeju Air crash that killed 179 people last month have found feathers in both engines, according to South Korean media reports, with a bird strike being examined as one possible cause.