Three youths were killed on the spot near Porayar in Nagapattinam district Sunday when the bike they were riding was involved in a head-on collision with an omni bus, said police.
The mishap happened when the omni bus bound for Nagapattinam from Chennai was negotiating a curve on the Villupuram-Nagapattinam stretch of the national highway.
A case has been registered and the bus driver arrested.