The Mumbai Police on Monday arrested three people after fire broke out in a nine-storey commercial building in Goregaon on Sunday killing four, PTI reported. The deceased were contractual workers deployed by a firm called Pratham Enterprises.

The police said prima facie investigations have revealed that a short circuit in an electric duct may have been the cause of fire. While three workers died late last night, another died early this morning. Several others were rescued.

The workers were hired to remove a private telecom firm’s assets on the seventh and eight floors of Technic Plus One building as part of a Bombay High Court order. The fire was initially declared a Level 2 fire, but was later classified as a Level 3 fire. Eight fire engines, six tankers and senior fire brigade officials were sent to control the blaze.

The police have booked an employee of Pratham Enterprises, and two labour contractors under relevant sections of the Indian Penal Code, including culpable homicide, Senior Inspector (Goregaon) Dhanaji Nalawade said according to PTI.

The Brihanmumbai Municipal Corporation said it will inspect the building. “We will have to check our records and carry out an inspection to see if there were any irregularities,” Assistant Municipal Commissioner Chanda Jadhav said. “We are awaiting a report from the fire brigade.”