A raging typhoon grounded two Chinese fishing boats in waters off South Korea's southern island of Jeju Tuesday, with four crew members confirmed dead and 12 still missing, South Korea's Coast Guard said.

A total of 33 crew members were aboard the two vessels, 17 on one and 16 on the other, when they were crippled in waters about

1.8 kilometers from the port of Hwasun in Jeju's Seogwipo around 2:40 a.m. amid gale-force winds and high waves caused by Typhoon Bolaven, the coast guard said.

The accidents were reported to authorities by two crew members after they reached the island. Both were taken to hospital as one had sustained serious injuries and the other complained of difficulty breathing.

Ten more crew members were rescued soon after and four bodies recovered, officials said.

Five crewmen confirmed to be on one of the boats that grounded are expected to be rescued soon.

The other boat, which broke into two pieces, is stranded in waters near the port of Hwasun and 12 crew members from that boat are unaccounted for.

The Coast Guard initially thought the two boats had sunk but later corrected that report after confirming the boats had grounded near the shore.

The Chinese consul stationed on Jeju Island has been notified of the accidents, they added. (Yonhap News)