A South Korean-flagged chemical tanker has capsized off the coast of Yamaguchi prefecture in western Japan, with seven deaths confirmed, public broadcaster NHK reported on Wednesday, citing the coastguard.

The tanker, Keoyoung Sun, was anchored due to bad weather and requested assistance after 7:00 a.m. on Wednesday (2200 GMT on Tuesday), reporting the vessel was tilting over, NHK reported.

The vessel had 11 crew aboard. Of the nine crew members retrieved, seven have been confirmed dead, with rescue operations ongoing for the remaining two, NHK reported.

The tanker was carrying 980 tonnes of acrylic acid, but no spillage has been detected, NHK reported.