Terrified patrons run for their lives as ceiling caves in on South Korean restaurant

Twelve people have been injured after a ceiling collapsed and crashed down on diners in a busy South Korean restaurant.

Around 40 people were inside the restaurant in Chungnam on Sunday when the accident occurred, local news channel SBS reports.

CCTV footage shows booths of patrons quietly eating before the ceiling starts to shake, triggering mass panic below.

Diners and restaurant staff begin to run for lives as a large air conditioning duct falls from above and the entire ceiling caves in.

One diner described "the sound of a firecracker exploding" just before the collapse was triggered.

Authorities are still investigating what caused the accident.