Thiruvananthapuram: A tourist bus overturned at Navayikulam in Kallambalam, leaving at least17 students and teachers injured, two of them critically. 

The students involved were MBA students of Sahrdaya College of Engineering, Kodakara, Thrissur. They were on a study tour from the college to the Vizhinjam port. Preliminary assessment suggests that the driver may have fallen asleep at the wheel. A total of 42 students and teachers were on board the bus.

The accident occurred around 3.30 am when the bus, travelling on the National Highway service road at Ethukkad near Navaikulam, lost control, rammed into a house and overturned, police said. There was minor damage to the house, but the family living in it was safe.

Residents rushed to the spot and helped rescue the stranded passengers, who were later shifted to a hospital in Parippally, police said. Of the injured, one person sustained serious injuries and was later shifted to a hospital in Kollam, police added.

Police have launched an investigation to ascertain the cause of the accident. Officials said CCTV footage from the bus would be examined as part of the probe.