South Korean divers have rescued four people and are looking for at least five others believed to be trapped inside a Chinese fishing boat that capsized near a small southwestern island.

An official from the Ministry of Public Safety and Security said Wednesday another man pulled from the boat was feared to be dead.

He says divers believe five other passengers are still inside the boat, which wasn't approved by South Korean authorities to fish in the country's waters.

The official spoke on condition of anonymity, citing office rules.

The accident occurred near a spot where a ferry sank in 2014 and killed more than 300 people, mostly teenagers on a school trip, in what was the country's largest maritime disaster in decades.