The passenger boats overturned Sunday afternoon on a river in Qianxi city, Guizhou province, state broadcaster CCTV said, sending 84 people into waters.

As of Monday morning nine were dead, 70 have been hospitalised and four were unharmed, state media said. One remains missing.

Chinese President Xi Jinping urged "all-out efforts" in the search and rescue operations and treatment of those injured, state news agency Xinhua said.

Xi also "underscored the importance of strengthening safety measures in tourist attractions" and other large public venues, the agency said.

Vice Premier Zhang Guoqing was dispatched to the scene to oversee the rescue efforts, state media added.

An investigation has found the boats were not overloaded with passengers, CCTV said.

Sunday's incident comes just over two months after 11 people were killed in a boat collision in central China.

The accident in Hunan province occurred when a passenger boat struck an industrial vessel, throwing 19 people overboard.