Kolkata: A 40-year-old worker of a knife manufacturing unit died on Tuesday afternoon, when a grinding wheel on which he was working, exploded at the workshop in Taltala, police officials said.Shailendra Sharma was working at the shop on 1 Smith Lane also known as Tyre Lane, when the stone grinding wheel exploded around 3:35 pm.Rajesh Kumar, a local shopkeeper said, "We found Sharma severely injured. He was bleeding profusely from the upper portion of his body."Locals transported Sharma to the nearest hospital, but he was pronounced dead on arrival. The exact cause of death is not yet determined, said cops, stating prima facie it seems like a case of accidental death. "We are taking all necessary steps to investigate the circumstances that led to this incident," said inspector Amit Roy of Taltala police station. — Dwaipayan Ghosh