At least two people were killed and four others were killed in a blast at a chemical factory in Thane's Bhiwandi on Wednesday night.
According to reports, the explosion took place in a nitrogen cylinder at the factory.
Over 300 labourers work at the factory, however, it was not clear how many of them were present at the site when the blast took place.
Relief and rescue work were on till the reports last filtered in.
More details are awaited.