MADURAI: Three workers died of asphyxiation after inhaling toxic gas while cleaning a ballast tank of a barge at the Old Harbour in Thoothukudi on Wednesday.

According to sources, G George Sharon of Uvari opened the cover and stepped inside to clean the tank. When he did not surface, Sandeep Kumar (22), a migrant worker from Rajasthan, entered the ballast tank. However, he too did not come up. Then another worker, T Geniston (35) of Punnaikayal in Thoothukudi, got inside the tank. Like the others, he too did not come out of the tank.

Based on an alert, Fire and Rescue Services personnel with lifesaving equipment entered the tank and found the workers lying unconscious at the bottom. The rescue personnel tried to resuscitate the workers, but their efforts were in vain. Their bodies were sent to Thoothukudi GH for post-mortem examination. The Tharuvaikulam Marine police have filed a case, sources said.