People watch as a crane lifts a bus from Narmada canal near Bodeli village, 180 km south of Ahmadabad, India, yesterday. [AP]

A bus veered off a bridge and plunged into a canal in western India yesterday, killing at least 44 school children and three adults, police said.

Their bodies have been recovered, but some children were still missing, said R.K. Patel, a senior police officer in Gujarat state. Four children were rescued.

The accident occurred in Vadodara, about 90 km southwest of Ahmedabad, Gujarat's main city.

The public bus was carrying more than 60 children and some passengers from three villages in the region, officials added.

They said the driver lost control after one of the tyres burst and ploughed through a concrete railing on the bridge plunging the bus into the canal.

"I was sitting in the last seat and suddenly I felt the bus going down," said Sunil Thakore, 13.

"I could see everything floating outside, and tried to call but there was no one around. I tried to pull my friend along, but it was impossible for me to swim with him."

The driver of the bus, an assistant and a woman were among the dead, police said.