Beijing: Authorities in China have confirmed 21 people have died after a tugboat sank on a trial voyage on the Yangtze, the country's longest river.

The vessel was raised on Saturday, 40 hours after it sank while undergoing testing with 25 people, including eight foreigners, aboard in the eastern province of Jiangsu on Thursday afternoon, state media said.

A sunken tug boat is lifted from the Yangtze River by a rescue team near Jingjiang, Jiangsu province in China. Credit:Reuters

Three people have been rescued, Xinhua news agency said, with one still missing. All those on board were male.

Rescuers were still searching the cockpit of the newly-built boat and along the river for the missing person, the report said, without giving his nationality.