HEFEI - Four people died and 21 others were injured after a truck loaded with fireworks collided with another vehicle and exploded on a highway in East China's Anhui province, local authorities said Wednesday.

A firefighter works to clean the debris after a truck loaded with fireworks collided with another vehicle and exploded on a highway in East China's Anhui province on March 27, 2012. [Photo/CFP]

The blast, which occurred at 5:00 pm Tuesday, also destroyed 100 nearby homes and damaged another 564 in Lujiang county, according to a statement released by the county government's information office Wednesday afternoon.

Fireworks on the truck were ignited in the collision, killing the drivers of both vehicles and two passengers on the spot, said the statement.

The explosion also injured 21 villagers nearby. Three were severely wounded, including one who remained in a deep coma Wednesday, it said.

Authorities are still investigating the cause of the accident.

The truck loaded with fireworks is completely destroyed after it collided with another vehicle and exploded on a highway in East China's Anhui province on March 27, 2012. [Photo/CFP]