Five persons were killed and 18 injured when an under construction staff quarters of the Central University collapsed here in Tiruvarur on Sunday, police said.
The toll could increase as several of the injured were in a serious condition, they said.
Police and fire service personnel were searching whether more persons were trapped in the debris.
A team of doctors had been rushed to the spot to give treatment and first aid, police said.
Some of the seriously injured have been rushed to Thanjavur government hospital.