A passenger opened an emergency exit on an Asiana Airlines flight as it was preparing to land on Friday, the carrier told AFP, adding that the plane landed safely but several people were hospitalised.
The plane was carrying nearly 200 passengers as it approached the runway at Daegu International Airport in South Korea, about 240 kilometres (149 miles) southeast of Seoul, on a domestic flight.
When the plane was around 200 meters (650 feet) above the ground, a passenger sitting near the emergency exit "opened the door manually by touching the lever", the carrier's representative told AFP.
The incident caused some passengers to have breathing difficulties, and several people were taken to a hospital after the landing, Asiana said, adding that there were no major injuries or damage.
Daegu police told AFP that they had taken in a man in his 30s for questioning over the incident.
South Korea's transport ministry said 12 people had been taken to hospital after the plane landed to deal with "discomfort and breathing issues".
The ministry confirmed that the plane door had been deliberately opened by a passenger while the plane was still in flight.
"Police are questioning him jointly with the land and transport ministry over aviation safety laws violations," they said in a statement.
"Under these laws, a person who opens a plane door without authorisation is subject to a maximum sentence of 10 years in prison."
A short video of the incident shot by a passenger on board the Airbus A321-200 was broadcast by South Korea's Yonhap News Agency.
The footage showed wind ripping through the open door in mid-air, with fabric seat-backs and passengers' hair flapping wildly as some people shouted in surprise.
Another video shared on social media showed passengers sitting in the emergency exit row next to an open door being buffeted by strong winds.
The two male passengers, wearing their seatbelts, were wincing as the wind whipped around them, while they clutched the armrests and tried and turn away from the door.
A 44-year-old passenger told Yonhap that it was "chaos" on the flight after the door was opened.
"It was chaos with people close to the door appearing to faint one by one and flight attendants calling out for doctors on board through broadcasting while others were running down the aisle in panic," the passenger said.
"I thought the plane was blowing up. I thought I was going to die like this."
A transport ministry official on the aviation safety team told AFP that this was "the first such incident" they were aware of in Korean aviation history.
South Korea's aviation industry has a solid track record for safety, experts say.
Asiana, which was established in 1988 as a rival to flag carrier Korean Air, was involved in a major crash in San Francisco in July 2013.
At that time, Asiana Flight 214 from Seoul clipped a sea wall with its landing gear, then crashed and burst into flames, killing three people and leaving 182 injured.
The troubled carrier is currently set for a takeover by Korean Air, which said in 2020 that it would buy out Asiana for $1.6 billion as the Covid pandemic wreaked havoc on the worldwide aviation industry.
