SEOUL, South Korea — A jetliner skidded off a runway, slammed into a concrete fence and burst into flames Sunday in South Korea after its landing gear apparently failed to deploy. All but two of the 181 people aboard were killed in one of the country’s worst aviation disasters, officials said.

The Boeing 737-800 operated by Jeju Air plane arrived from Bangkok and crashed while attempting to land in the town of Muan, about 180 miles south of Seoul.

Footage of the crash aired by South Korean television showed the plane skidding across the airstrip at high speed, evidently with its landing gear still closed, and slamming into the wall, triggering an explosion and generating plumes of thick, black smoke.

The crash killed 179 people, the South Korean fire agency said. Emergency workers pulled two crew members to safety. They were conscious and did not appear to have any life-threatening injuries, health officials said.

The chief of the Muan fire station, Lee Jeong-hyeon, told a televised briefing that the plane was completely destroyed, with only the tail assembly still recognizable in the wreckage. Officials were investigating the cause of the crash, including whether the aircraft was struck by birds, Lee said.

The control tower issued a warning about birds to the plane shortly before it intended to land and gave the crew permission to land in a different area, Transport Ministry officials said. The crew sent out a distress signal shortly before the crash, officials said.

Investigators retrieved the jet’s flight data and cockpit voice recorders, said senior Transport Ministry official Joo Jong-wan. He said it may take months to complete the probe into the crash. The runway will be closed until Jan. 1, the ministry said.

Video of the crash indicated that the pilots did not deploy flaps or slats to slow the aircraft, suggesting a possible hydraulic failure, and they did not manually lower the landing gear, suggesting they did not have time, said John Cox, a retired airline pilot and CEO of Safety Operating Systems in St. Petersburg, Florida.

Despite that, the jetliner was under control and traveling in a straight line, and damage and injuries likely would have been minimized if not for a barrier being so close to the runway, Cox said.