The number of people killed in a tanker truck explosion on a highway in eastern China has climbed to 19, with more than 170 injured, local authorities said Sunday.

The force of the blast on Saturday afternoon caused nearby homes and factories to collapse, and sent huge clouds of black smoke billowing into the air as flames engulfed several cars.

Local government authorities said Sunday afternoon there were 172 people injured in the accident near Wenling city in the eastern province of Zhejiang.

China's emergency management department had earlier said there were 189 injured people being treated in hospital.

Dramatic video footage of the accident published by state media showed a huge ball of fire shooting into the air as people screamed.

In one clip, a large piece of debris is seen flying into the air before crashing on some nearby buildings.

Another video showed the remains of the tanker and several truck tyres smashed into a building, which had been reduced to rubble.

Local authorities said the truck was loaded with liquefied gas.

State news agency Xinhua reported Sunday that there was a second blast when the truck fell onto a workshop near the expressway after the first explosion.

Emergency responders were still conducting search and rescue operations, it added.

Deadly road accidents are common in China, where traffic regulations are often flouted or not enforced.

Last year, at least 36 people died and 36 others were hurt in eastern China when a packed coach with a flat tyre collided with a truck.