Boeing backs down when South Korea requests inspection of the B737-800

Boeing Shares fell nearly 5% in pre-market trading Monday, after South Korea ordered checks on all B737-800 planes, the model involved in the deadly Jeju plane crash over the weekend.

Acting President Choi Sang-mok asked the Ministry of Transport to conduct an emergency safety inspection of the country's entire airline operating system, while officials at the Ministry of Land, Infrastructure and Transport (MOLIT) said they would conduct a “special comprehensive inspection” of the country's entire airline operating system. “B737-800.”

New York-listed Boeing shares fell 4.7% in premarket trading before paring losses to trade down 3.6% as of 6:45 a.m. ET.

Uncertainty surrounds the exact circumstances of the accident that killed 179 of the 181 people on board the plane on Sunday. The plane landed without the correct gear at Muan International Airport in South Korea, skidded off the runway and hit a wall before catching fire. The survivors were two crew members who were recovered from the wreckage.

At a news conference on Monday, Mullet said the plane's pilot reported a “bird strike,” just minutes after the airport control tower issued a warning about bird activity. The pilot also informed the control tower of a “spin,” referring to the aborted landing attempt, and announced “Mayday,” Yoo Kyung-soo, director of aviation safety policy at MOLIT, said, according to an NBC News translation.

The two black boxes were recovered from the plane and sent for analysis. Meanwhile, the US National Transportation Safety Board is leading a team of US investigators, including the Federal Aviation Administration and Boeing, to assist South Korea's Aviation and Railroad Accident Investigation Board in investigating the accident.

Mullet officials said on Monday that they were reviewing the concrete wall that the plane crashed into to determine its connection to the accident.

They also said they would conduct a “special, comprehensive inspection of the B737-800.”

Boeing's popular narrow-body jet has been in operation for nearly three decades, its development being preceded by the American manufacturer's B737-Max jets, a later version of the model.

The B737-800 aircraft are widely used by South Korean low-cost carriers, with Jeju Air being the largest operator with 39 aircraft, MOLIT said on Monday. Other airlines include T'way Air, Jin Air, Eastar Jet and Air Incheon, while Korean Air has two of these.

“We will examine compliance with various regulations, including operational records and inspections and maintenance conducted before and after flights,” Jo Jung-wan, director of MOLIT’s Aviation Policy Office, said Monday, according to an NBC News translation.

“We plan to review strengthening regulations regarding bird strikes, which have been identified as a potential cause of the accident, especially for new airports under construction.”

A Boeing spokesperson told CNBC: “We are in contact with Jeju Air regarding Flight 2216 and stand ready to support them. We extend our deepest condolences to the families who lost loved ones, and our thoughts remain with the passengers and crew.”

Local media reported that another Jeju Air plane of the same model returned to South Korea's Gimpo Airport shortly after take-off on Monday after reporting problems with its landing gear.

At a press conference on Sunday, Jeju Air's administrative support office head, Sung Kyung-hoon, said the airline would support the victims and their families, and that the plane was covered by $1 billion in insurance, according to the Yonhap news site. .

Song also denied that mechanical failures or inadequate security preparations played a role in the accident.

“This accident is not related to any maintenance issues. There can be absolutely no compromise when it comes to aircraft maintenance,” Song said.

Jeju Air shares hit an all-time low on Monday, according to FactSet data, closing down 8.65%.

— CNBC's Yu Boon Peng contributed to this story.