Three workers were killed and six injured after a fire broke out and caused a blast in a food processing unit in the Narela Industrial Area in the early hours of Saturday, the Delhi Police said.

The police received a distress call at 3:35 am about the fire at the factory of Shayam Kripa Foods Private Limited, which processes dry moong dal, it said.

The fire engulfed the factory, trapping some workers inside, a police officer said.

Fourteen fire tenders were pressed into service and the blaze was doused by noon, a Delhi Fire Services official said.

He said nine people were rescued from the building and admitted to Satyawadi Raja Harish Chandra Hospital in Narela.

The police officer said three of them -- Shyam (24), Ram Singh (30) and Beerpal (42) -- were declared dead while the others are undergoing treatment.

The injured -- Pushpender (26), Akash (19), Mohit Kumar (21), Ravi Kumar (19), Monu (25) and Lalu (32) are undergoing treatment at Safdarjung Hospital for burn injuries, he added.

Preliminary investigations suggest that the blaze started after a gas leak from one of the pipelines. The pipelines supplied gas to burners used for roasting the moong dal, the officer said.

As the fire spread, it caused the compressor to overheat, resulting in a blast, he said.

The factory owners have been identified as Rohini residents Ankit Gupta and Vinay Gupta.

A case is being registered under appropriate sections and investigation taken up, the officer said.

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