SEOUL - Four Chinese fishermen are confirmed dead and eleven others are still unaccounted for after a powerful typhoon sank their fishing boats in South Korean waters early Tuesday morning.

Photo of "Yuejiangchengyu" No. 91104 from Weihai city of East China's Shandong province on Aug 27. Two fishing boats, "Yuejiangchengyu" No. 91104 and No. 91105, both from Weihai city of East China's Shandong province, capsized around 2:40 am local time in waters about 1.8 kilometers from South Korea's port of Hwasun in Jeju's Seogwipo. [Photo/Xinhua]

Two fishing boats capsized around 2:40 am local time in waters about 1.8 kilometers from the Hwasun port in Jeju's Seoguipo city due to heavy winds and high waves unleashed by Typhoon Boleven.

Two crew members swam ashore and reported the accident to authorities, and sixteen others were rescued later by South Korean coast guard officials. Four were found dead, putting the number of those missing at 11.

The vessels, "Yuejiangchengyu" No.91104 and No.91105, are both from Weihai city of East China's Shandong province.

The Jeju-based Chinese Consulate is maintaining close contact with local police in search and rescue efforts.

A typhoon alert was issued in waters off the southern resort island early Monday morning. Schools there were closed and flight services canceled.