More than 32 people including children were killed yesterday when a blaze at an eastern Indian fireworks factory set off explosions so powerful that the building collapsed.

Thirty-two bodies were pulled from the wreckage of the factory in Khusropur village, 35km east of the Bihar state capital Patna, district magistrate B Rajendra said.

"We expect to recover more bodies when we clear the debris," Rajendra said.

At least 20 people were injured, many critically, in the explosions and fire, the Press Trust of India said.

Many children's bodies were piled in three-wheel scooters and small vans and were transported to hospital in Patna for post-mortems, Ranjan Rahi, a photographer, said.

Relatives wailed as the dead bodies were pulled from the wreckage.

The explosions were so powerful that the roofs and walls of the building caved in, trapping people inside.

While some burnt to death, others died inhaling toxic fumes or were crushed to death by falling debris.

Police, residents and relatives dug through the debris seeking more victims.

The workers were making fireworks before India's main religious festival season when the explosion occurred.

Police said a huge quantity of explosive materials, gas cylinders and powerful firecrackers was in the factory at the time.

An electrical short-circuit was believed to have sparked the fire, officials said. More than 100 people were believed to have been in the factory when the blaze broke out, they said.

Fires are common at firecracker factories in India due to lax safety standards. Children are often employed as cheap labour even though Indian law forbids it.

Groups fighting child labour say India's firecracker industry employs at least 50,000 children.

"We are investigating the licence of the factory," Rajendra said.

Fire trucks battled for over two hours to control the blaze, Senior Superintendent of Police Kundan Krishnan told reporters.

Efforts to control the flames were hampered by frantic relatives who jammed narrow lanes leading to the factory, looking for missing family members.

PHOTO CAPTION

Police officers and rescue workers take the bodies of children who died in a fire at Khusrupur village, about 35 kilometers east of Patna, India, Thursday, Sept. 15, 2005. (AP)