More than 170 killed after South Korean jet crashes at airport. Here’s what we know

Dozens of people were killed Sunday when an airliner crashed at an airport in southwestern South Korea, skidding down the runway on its belly before bursting into flames.

At least 177 people have so far been confirmed dead, according to the local fire department. Two people, both crew members, were pulled alive from the crash site, meaning only two of the 181 people on board the plane are unconscious.

It is the deadliest aviation disaster to hit South Korea since 1997, when a Korean Airlines Boeing 747 crashed in the Guam jungle with the loss of 228 lives.

What happened?

Jeju Air flight 7C 2216 from Bangkok was carrying 175 passengers and six crew members when the disaster struck at the airport in Muan county, on the country’s southwestern tip, just after 8 p.m. 9 local time Sunday (7 p.m. ET Saturday).

Footage of Sunday’s crash broadcast by several South Korean news outlets showed the plane sliding on its belly at high speed, hitting an embankment and erupting into a fireball.

Neither the rear nor the front landing gear were visible in the footage – broadcast by networks including YTN, JTBC and MBC – as smoke poured from the back of the gliding aircraft.

Firefighters were later seen using water cannons to extinguish the flaming wreckage of the plane, which was listed as a Boeing 737-800 on flight tracking site FlightAware. Several parts of the plane were also seen scattered across the runway.

The victims include 82 men, 83 women and 12 people whose gender could not be determined, according to the South Jeolla Fire Service. Both survivors were crew members, a man and a woman, according to the rescue team.

Two Thai nationals were among those on board, according to South Korea’s Land Ministry. All the other passengers were South Korean.

What caused the accident?

Experts told CNN that the plane’s undercarriage — specifically, the wheels used for takeoff and landing — did not appear to be fully deployed before landing. But what caused this lack of implementation remains unclear.

Aviation analysts said more evidence is needed before South Korean authorities can definitively determine what could have caused Sunday’s crash, including speculation by local officials about a possible bird strike prior to the crash landing.

The comments came after Lee Jeong-hyun, the head of the Muan Fire Department, briefed the media that the cause was “estimated to be the occurrence of a bird strike or bad weather.” Footage of the crash showed clear skies at the time.

David Soucie, former safety inspector for the Federal Aviation Administration, said that “speculation is an investigator’s worst enemy.”

“In fact, that’s why it’s so protected when there’s a plane crash investigation, the information is protected. They’re not supposed to make any speculation about this type of thing,” Soucie told CNN’s Paula Newton.

Aviation industry consultant Scott Hamilton echoed Soucie’s concerns, urging South Korean authorities to “stop making statements” at this stage.

Sunday’s crash is “very puzzling” as both the plane and the airline have a strong safety record and flying conditions were excellent, an aviation journalist said.

The Boeing 737-800 is one of the most used aircraft in the world, and each plane is used for about four or five flights a day, Geoffrey Thomas, editor of Airline News, told CNN’s Paula Newton.

“It’s the most reliable aircraft in the world and it’s been in service for 20 years,” he said. “Everybody knows how it works. And it works really, really well. And the maintenance done in (South) Korea is as good as it gets anywhere in the world.”

“It is a little unclear whether the undercarriage collapsed on landing, or whether the undercarriage was not deployed at all. This is a really serious matter that investigators will obviously be very focused on, Thomas added.

He added “it is confusing” that the crash happened when it landed in dry and sunny conditions at a good airport.

The American aerospace giant Boeing has had one turbulent time in recent yearsincluding two 737 Max crashes, a tragedy that the company agreed to plead guilty defrauding the Federal Aviation Administration during the aircraft certification process.

However, analysts have described the Boeing 737-800 – an earlier and different model than the Max – as a reliable workhorse in the air with an extremely strong safety record.

Jeju Air’s chief executive said the plane had shown “no signs of trouble” before Sunday’s accident.

“At present, it is difficult to determine the cause of the accident, and we have to wait for the official announcement of the investigation by the relevant government agency,” Kim Yi-bae said during a press briefing at the airport.

Where is the investigation focused?

Officers from the National Incident Response Team had arrived to investigate what caused the accident.

According to a briefing from the Ministry of Land, the control tower had instructed the pilot to change course to land in the opposite direction, to avoid the potential bird strike. The pilot followed the instructions.

About a minute later, the pilot called the tower. The landing attempt took place about two minutes after the Mayday call, according to the ministry. Authorities are continuing their investigation.

The “black box” flight data recorder has been recovered by the accident investigation committee, while the voice recorder is yet to be recovered, ministry officials said.

Flight data recorders or so-called “black boxes” offer flight safety investigators critical facts when piecing together an incident.

More than 700 personnel from the police, military and coast guard have been mobilized to respond to the situation, the ministry added.

What do the authorities say?

South Korea’s acting president said the site of Sunday’s plane crash has been declared a special disaster zone as he promised a full investigation into what caused the deadly disaster.

“We will concentrate all resources on recovery and support for the victims. All necessary resources are being mobilized and a special disaster zone has been declared,” Choi Sang-mok said in a statement.

Choi, who traveled to the accident site on Sunday, extended his “heartfelt condolences to the bereaved families” and vowed to do everything possible to manage the aftermath of the incident and prevent similar accidents in the future.

The tragedy comes just two days into Choi’s term as acting president, the latest chapter in a time of political chaos in South Korea.

The country’s current president, Yoon Suk Yeol, was stripped of his powers by parliament two weeks ago following a brief martial law order that threw the country into political disarray. He is currently suspended while a high court decides his fate.

Han Duck-soo, the man who stepped in to replace Yoon as acting president, was impeached by parliament on Fridaymeaning that Choi – the finance minister and deputy prime minister – stood in for him.

What did the plane’s maker say?

Boeing offered its condolences to those who lost loved ones in the crash.

“We are in contact with Jeju Air regarding Flight 2216 and stand ready to support them,” Boeing said in a brief statement posted to its X account.

“We express our deepest condolences to the families who lost their loved ones and our thoughts remain with the passengers and crew,” the company added.

The American aviation giant has had one turbulent time in recent years, including two 737 Max crashes, a tragedy for which the company agreed to plead guilty to defrauding the Federal Aviation Administration during the certification process for the plane.

However, analysts have described the Boeing 737-800 as a reliable workhorse in the sky with a extremely strong safety record.

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