Bijnor (UP), Sep 12: At least six labourers died while two others were seriously injured in an explosion in a private petro-chemical factory here Wednesday morning, police said.

According to the police, one labourer is still missing. The blast took place around 8 am when the boiler of the factory was being repaired. "There was a blast in the Mohit Petro-Chemical Factory located on Nagina Road. In the blast, labourers Balgovind, Ravi, Lokendra, Kamalveer, Vikrant and Chetram died. Two labourers were brought to a hospital in a serious condition. One labourer is said to be missing." Superintendent of Police Umesh Kumar Singh told PTI.

"As per information gathered so far, the boiler of the factory was not functioning for the past few days. Today, while it was being repaired, there was a blast in the boiler while welding work was going on," he said. Singh said efforts are on to trace the owner of the factory.