SEOUL -- South Korea's acting President Choi Sang-mok on Sunday announced a week-long mourning period over a passenger jet that crashed while landing at the country's southwest airport.

Choi said during a central disaster countermeasures meeting that the government will set seven days until midnight on Jan 4 next year as the national mourning period while setting up joint memorial altars in 17 cities and provinces to express condolences for the victims.

He said civil servants in all ministries, local governments and public institutions will wear mourning ribbons during the period, vowing to thoroughly investigate the exact cause of the accident and take actions to prevent recurrence of such a tragic accident.

Choi expressed deep condolences to the deceased and their bereaved families, declaring Muan county as a special disaster area to provide necessary support for the bereaved families and the injured.

It was reported at about 9:03 am local time that the airplane with 175 passengers, including 173 South Koreans and two Thais, together with six flight attendants on board crashed while attempting to land at the Muan International Airport, some 290 km southwest of the capital Seoul.

The Jeju Air flight 7C2216 from Bangkok, Thailand landed without wheels, skidded off runway and hit the outer wall of the runway, with its fuselage broken in half and catching fire.

Only two crew members were rescued at the rear of the ill-fated aircraft, most parts of which were severely damaged.