A 33-year-old man, identified as Narayan Shetty, was arrested by the GRP after a bottle of chemical, he was allegedly carrying, broke inside an Ambernath-bound train.
A few passengers sustained burn injuries.
The police officers said that the bottle allegedly slipped and fell when the train was between Mulund and Thane, injuring six, including the bottle’s owner.
The train reached Thane at 1.52 pm on Friday.
The injured were admitted to the Thane civil hospital.