At least 22 people were killed and other 18 were reported missing after three explosions occurred on Monday at a warehouse for refrigerated goods near Seoul.

Hundreds of firefighters rushed to put the fire out at the two-storey warehouse in Icheon, about 50 miles from the capital, AFP reports. 

Seventeen people out of the 57 workers on site were rescued and taken to the hospital. They were treated for burns and smoke inhalation.

An official said that due to the chemicals from the site the searching for victims was hampered. 

Official Kim Jung-geun said that 500 firefighters were deployed to the site of the blaze and that they don’t have control over the fire due to the smoke that is coming out of the basement, Houston Chronicle said.

According to the United Press International, the warehouse is owned by Korea 2000. The company was planning to open the warehouse next weekend.

Firefighters believe that the cause of the accident were the vapors from the refrigerant gases pumped by workers which ignited in the engine room situated at the basement of the facility.

According to Provincial Fire Chief Choi Jin-jong, the three explosions occurred at an interval of 10 seconds before the building was taken up by flames.

He said: “We are having hard time putting down the blaze due to a series of explosions at the time of the fire, which demolished all firefighting facilities in the basement.”