Batam. A deadly explosion rocked the ASL Shipyard in Tanjung Uncang, Batam, on Wednesday morning, killing at least 10 workers and injuring more than a dozen others, after a tanker under repair caught fire during maintenance work.

The blast occurred aboard the MT Federal II, a tanker that was reportedly still undergoing repairs when it suddenly exploded and burst into flames. Police and emergency teams rushed to the scene to extinguish the fire and recover victims trapped inside the vessel.

Riau Islands Police Chief Insp. Gen. Asep Syafrudin confirmed that as of Wednesday afternoon, 10 workers were confirmed dead and 18 others were seriously injured. “The cause of the explosion is still under investigation,” Asep told reporters, adding that forensic teams from the provincial police and Batam City’s criminal unit were conducting a detailed examination at the site.

Authorities have yet to determine what triggered the blast, which sent plumes of thick smoke rising above the industrial zone in western Batam. The victims were employees of ASL Shipyard, one of the largest shipbuilding and repair facilities in the region.

The injured workers have been taken to several hospitals across Batam, including Mutiara Aini Hospital, Embung Fatimah General Hospital, Graha Hermine Hospital, and Elizabeth Hospital. Families of the victims gathered at the Aini Hospital morgue, many in tears as they awaited identification of their loved ones.

Wednesday’s explosion marks the second fatal incident involving the Federal II at the same shipyard this year. In late June, a separate explosion on the same vessel killed five workers.