At least 40 school children were killed on Wednesday when their bus veered off a bridge and plunged into a canal in western India, police said. Their bodies have been recovered, but more than 20 children were still missing, said R.K. Patel, a senior police officer in Gujarat state said. Four children were rescued. "The death toll could go up, " he was quoted as saying by Reuters. The accident occurred in Vadodara, 55 miles southwest of Ahmedabad, Gujarat's main city. The bus was carrying more than 60 children to their school, officials added.