Police on Thursday arrested the main accused in the illegal firecracker factory blast case, a day after six persons were killed in the incident at Bareilly in Uttar Pradesh.

Senior Superintendent of Police Anurag Arya said the explosion occurred at Rehman Shah's home, destroying several houses in the area.

Police arrested alleged mastermind Nasir Shah on Thursday and sent him to jail, Arya added.

The SSP said it has been found in the preliminary investigation that Shah, who has a license to only sell firecrackers, was operating an "illegal" firecracker factory at the residence of Rehman Shah, his father-in-law, where the incident occurred.

The bodies of two kids, aged four and five, were pulled from the rubble of a firecracker factory which was destroyed in an explosion here while one of the injured Sitara (32) succumbed to her injuries at hospital, taking the death toll to six, police said on Thursday.

The blast in the manufacturing unit located in the district's Sirauli area occurred on Wednesday and three people were initially declared dead. The bodies of the children were found under the debris late in the night during a search operation.

After the incident, Senior Superintendent of Police Anurag Arya suspended four police personnel, removed the local station house officer and ordered a probe against the circle officer concerned.

The explosion in the factory also caused damage to some adjoining buildings.

District Magistrate Ravindra Kumar said the administration and police were investigating every angle and all five injured were undergoing treatment.

"One person is still missing. It is feared that he/she too might be trapped under the debris," he added.

Along with the local rescue teams, the State Disaster Response Force is also engaged in the rescue work.

The deceased have been identified as Tabassum (44), Rukhsana (28), Hasan (4) and Shahjahan (5). One woman is yet to be identified.

Police said they were verifying the licence of the unit.

The four policemen suspended are Sub-Inspectors Deshraj Singh and Nahar Singh and Constables Ajay and Surendra.

Sirauli SHO Ravi Kumar has been removed and sent to Police Lines, and a probe ordered against Circle Officer Gaurav Singh, they said.

A senior police officer said factory operator Nasir allegedly had a licence for another place but the house where the incident occurred belonged to his in-laws.

"The explosion also caused damage to at least three adjoining buildings. Nasir is said to have a licence, but its details are being looked into," IG Rakesh Singh said.

Chief Minister Yogi Adityanath offered his condolences to the kin of the dead and directed officials to ensure proper treatment of the wounded.

"We have recovered remains of locally made crackers from the spot. Prima facie, it appears that the blast occurred because of them," Arya said, ruling out any deliberate act.

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