Four persons including a van driver and two women workers were killed in a road accident at Sevugampatti Pass on the Batlagundu-Dindigul highway on Monday.
The van, which was heading to a private mill with about 15 workers, collided with a TNSTC bus bound for Theni from Dindigul.
Police said that eight others travelling in the van were said to be critical and have been rushed to Government Rajaji Hospital Madurai, while 54 passengers in the bus were taken to Batlagundu GH for first aid and later transported to the Government Medical College Hospital, Theni.
Nilakottai DSP Murugan, Tahsildar Subbiah and police from Pattiveeranpatti station, along with Batlagundu Station Fire Officer Vivekanandan and emergency ambulance services helped the passengers to get out of the bus.
The bodies of the four workers including the van driver were sent to the GH for post-mortem examinations.
The victims who were killed were identified as Suresh (van driver), Latha, Suguna and Kalidas, a police officer said.
Preliminary inquiries with some of the passengers indicated that a possible burst of a tyre in the bus may have led to loss of control of the vehicle. Being a working day, the TNSTC bus had a full complement of passengers.
The workers were heading to a mill in Singarakottai, near Batlagundu. Further investigations are on.