A South Korean-flagged tanker capsized on Wednesday morning in waters off the western Japanese prefecture of Yamaguchi.

The Japan Coast Guard says six of the 11 crew were rescued. It is continuing rescue operations with aircraft and a patrol vessel.

The local coast guard station says it received a distress signal at a little past 7 a.m. from the chemical tanker Keoyoungsun in waters west of Mutsurejima, an island that is part of Shimonoseki City. The tanker was reportedly tilting.

The coast guard says the tanker had been at anchor due to rough weather. Two South Koreans, eight Indonesians and a Chinese were on board.

Winds clocking 36 to 54 kilometers per hour were blowing in the sea area with waves reaching as high as 3.5 meters. Shimonoseki City registered a maximum wind velocity of about 82 kilometers per hour early Wednesday morning.