A fire has broken out on a foreign-flagged cargo ship docked at an eastern Chinese port, causing heavy casualties, according to state media.

President Xi Jinping called for urgent search and rescue efforts and a swift investigation.

Premier Li Qiang called for “trapped” people to be rescued and stressed the need to “prevent secondary disasters”.

The vessel was undergoing maintenance at a shipyard in the city of Qingdao when the blaze occurred at 11:15 local time (03:15 GMT), state news agency Xinhua said.