Muan, Jan 2 (IANS): South Korean Police on Thursday raided Muan International Airport, the office of Jeju Air and other locations over the airline's deadly crash that killed 179 people, as they stepped up their probe into the worst aviation disaster on the nation's soil.

The Jeonnam Provincial Police conducted search and seizure operations at the airport in southwest South Korea, the Seoul office of Jeju Air, and the Muan office of the Busan Regional Office of Aviation, officials said.

The search warrant was issued on charges of professional negligence resulting in death, officials said.

Police are securing evidence related to the legitimacy of the airport's localiser, a concrete wall housing an antenna array located near the runway at the time, and the communication record between the control tower and the pilot shortly before the plane crash.

On Sunday, the Jeju Air passenger jet from Bangkok crashed into the outer wall of Muan International Airport during a belly landing, leaving 179 of the 181 people on board dead.

The plane skidded along the ground without its landing gear deployed, crashing into a concrete wall before bursting into flames with a deafening explosion. It marked the deadliest aviation accident ever on the nation's soil.

The airport control tower reportedly warned of a bird strike minutes before the pilot declared mayday and landed the plane without its landing gear, according to the Land Ministry.

Police investigations will centre around whether there were any problems in the emergency landing process, including the measures taken by the airport tower controller.

The identities of all 179 victims have been identified as of Wednesday, and authorities are working to match the damaged body parts with the victims through DNA analysis.

As of Thursday morning, the bodies of 24 victims were delivered to their families and the funeral process was underway for 10 of them, officials said.

Authorities have also begun delivering some of the victims' belongings collected from the scene to the respective family members.

Nearly 158,000 people came by the joint memorial altars set up across the nation to pay their respects to the victims.

Meanwhile, the Land Ministry's Aviation and Railway Accident Investigation Board said Thursday it had completed converting the data from the Cockpit Voice Recorder into an audio file.

The black boxes, or Flight Data Recorder, retrieved from the crashed plane were to be sent to the US for analysis due to damage sustained from the accident.