South Korea’s authorities investigating last month’s Jeju Air plane crash have submitted a preliminary accident report to the UN aviation agency and to the authorities of the United States, France and Thailand,

South Korea released on Monday a preliminary report on its investigation into a Jeju Air crash on Dec. 29 at Muan International Airport that killed 179 people in the deadliest air disaster on the country's soil.

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