A passenger plane burst into flames Sunday after it skidded off a runway at a South Korean airport and slammed into a concrete fence when its front landing gear apparently failed to deploy, killing at least 120 people, officials said, in one of the country's worst aviation disasters.

The National Fire Agency said rescuers raced to pull people from the Jeju Air passenger plane carrying 181 people at the airport in the town of Muan, about 290 kilometers (180 miles) south of Seoul. The Transport Ministry identified the plane as a 15-year-old Boeing 737-800 jet and said the crash happened at 9:03 am local time.

At least 120 people — 57 women, 54 men and nine others whose genders weren't immediately identifiable — died in the fire, the fire agency said. The death toll is expected to rise further as the rest of the people aboard the plane remain missing about six hours after the incident.

Emergency workers pulled out two people, both crew members, to safety, and local health officials said they remain conscious. The fire agency deployed 32 fire trucks and several helicopters to contain the fire, it said.

Footage of the crash aired by YTN television showed the Jeju Air plane skidding across the airstrip, apparently with its landing gear still closed, and colliding head-on with a concrete wall on the outskirts of the facility. Other local TV stations aired footage showing thick pillows of black smoke billowing from the plane engulfed with flames.

Lee Jeong-hyeon, chief of the Muan fire station, told a televised briefing that rescue workers are continuing to search for bodies scattered by the crash impact. The plane was completely destroyed, with only the tail assembly remaining recognizable among the wreckage, he said.

Workers were looking into various possibilities about what caused the crash, including whether the aircraft was struck by birds that caused mechanical problems, Lee said. Senior Transport Ministry official Joo Jong-wan separately told reporters that government investigators arrived at the site to investigate the cause of the crash and fire.

Emergency officials in Muan said the plane's landing gear appeared to have malfunctioned. The Transport Ministry said the plane was returning from Bangkok and its passengers include two Thai nationals.

Thailand's prime minister, Paetongtarn Shinawatra, expressed deep condolences to the families of those affected by the accident through a post on social platform X. Paetongtarn said she had ordered the Ministry of Foreign Affairs to provide assistance immediately.

Kerati Kijmanawat, the director of the Airports of Thailand, confirmed in a statement that Jeju Air flight 7C 2216 departed from Suvarnabhumi Airport with no reports of abnormal conditions in the airspace or on the runway.

Jeju Air in a statement expressed its “deep apology” over the crash and said it will do its “utmost to manage the aftermath of the accident.”

In a televised news conference, Kim E-bae, Jeju Air's president, deeply bowed with other senior company officials as he apologized to bereaved families and said he feels “full responsibility” for the incident.

Kim said the company hadn't identified any mechanical problems in the aircraft following regular checkups and that he would wait for the results of government investigations into the cause of the incident.

Boeing said in a statement on X that it was in contact with Jeju Air and is ready to support the company in dealing with the crash.

“We extend our deepest condolences to the families who lost loved ones, and our thoughts remain with the passengers and crew,” Boeing said.

It's one of the deadliest disasters in South Korea's aviation history. The last time South Korea suffered a large-scale air disaster was in 1997, when a Korean Airline plane crashed in Guam, killing 228 people on board. In 2013, an Asiana Airlines plane crash-landed in San Francisco, killing three and injuring approximately 200.

Sunday's accident was also one of the worst landing mishaps since a July 2007 crash that killed all 187 people on board and 12 others on the ground when an Airbus A320 slid off a slick airstrip in Sao Paulo and collided with a nearby building, according to data compiled by the Flight Safety Foundation, a nonprofit group aimed at improving air safety.

In 2010, 158 people died when an Air India Express aircraft overshot a runway in Mangalore, India, and plummeted into a gorge before erupting into flames, according to the safety foundation.

The incident came as South Korea is embroiled into a huge political crisis triggered by President Yoon Suk Yeol's stunning imposition of martial law and ensuing impeachment. Last Friday, South Korean lawmakers impeached acting President Han Duck-soo and suspended his duties, leading Deputy Prime Minister Choi Sang-mok to take over.

Choi ordered officials to employ all available resources to rescue the passengers and crew before he headed to Muan. Yoon's office said his chief secretary, Chung Jin-suk, will preside over an emergency meeting between senior presidential staff later on Sunday to discuss the crash.