South Korean authorities are still investigating the cause of the recent air disaster at Muan International Airport. Some are blaming a concrete embankment at the end of the airport runway, which will now be removed.

Investigators have confirmed the presence of bird feathers and blood in both engines of the Jeju Air jet that crashed last month in South Korea, killing 179 people, according to a source familiar with the ongoing probe.

The Jeju Air 737 crash in South Korea on Sunday that killed all but two of the people onboard was in many respects as baffling as it was tragic. Given the scant information currently available, it’s hard even to piece together a coherent picture of what happened.

Seven airports will also have their runway safety areas adapted following a review of all South Korea's airports that was carried out after the crash - the deadliest in the country's history. The Jeju Air flight was bringing passengers home from Thailand after Christmas when it made an emergency landing at Muan airport and exploded after slamming into a concrete barrier at the end of the runway.

South Korea's transport ministry said on Wednesday that it would remove the concrete embankment installed at Muan International Airport following last month's Jeju Air crash, its deadliest domestic air disaster.