South Korea’s parliament passed a bill on Monday to launch an independent probe into the Jeju Air plane crash in December 2024 that killed 179 people in the deadliest air disaster on the country’s soil.

A panel made up of 18 members of parliament will investigate the possible causes of the crash, including whether enough was done against the risk of a bird strike, any engine or mechanical failures and an embankment that the plane struck at the end of the runway.

The inquiry will also investigate whether government agencies tried to cover up or downplay anything that was found during the official investigation, according to the bill.

A Jeju Air Boeing (BA.N), opens new tab 737-800 made a belly-landing at Muan airport without its landing gear down after an aborted landing, overshot the runway and slammed into an embankment, killing all but two of the 181 people on board as it erupted in a fireball.

An investigation by the government-led Aviation and Railway Accident Investigation Board had yet to produce a final report. It said in an interim report in January that the aircraft’s two engines sustained bird strikes.

In an update seen by Reuters in July, the board found the left engine had been shut down even though it sustained less damage than the right and could have kept the aircraft flying.

The embankment at the end of the runway that supported airport navigation equipment was found to be not in line with global standards that call for such a structure to be set up in a way that would easily give way in case of impact, experts say.

Most air accidents are caused by multiple factors and experts caution against putting too much weight on incomplete evidence.