Three buildings in western India (search) collapsed when a cooking gas cylinder exploded, killing at least 43 people, police said Monday.

Rescuers using dogs pulled out the bodies trapped beneath concrete slabs and mounds of debris, said V.K. Gupta, the police commissioner of Surat (search), the city where the blast occurred.

"The rescue work was over and the debris were being cleared," Gupta said.

He said the 3:30 a.m. explosion appeared to be accidental.

"Apparently it seems that it is not the handiwork of any terrorist organization," he said.

About 100 people worked and lived in the buildings, said Manoj Sorathiya, a nearby resident.

Heavy-duty cranes were used to help shift debris from the blast site, located in one of the city's most congested neighborhoods.

Surat, about 190 miles north of the Gujarat state capital, Gandhinagar (search), is a well-known center for the cutting and polishing of diamonds. Machines used for those purposes often are illegally fired by cooking gas cylinders.