One person was crushed to death and four others were seriously injured when the upper sheave of a crane attached to the hook suddenly snapped and came down crashing on workers at a check dam construction site in a village in the district.
Police said the check dam was being constructed by the state government across the Adappar river at Kallimedu village near Vedaranyam.
Police identified the deceased as Shankar Rao (28), a worker from Andhra Pradesh.
Police said work was going on when the upper sheave of the crane attached to the hook suddenly snapped. The hook was carrying load and the broken portion fell down on the workers standing in the vicinity.
The injured workers belong to Odisha.
They have been admitted to the Nagapattinam government hospital.