Over 40 children were injured on Wednesday night when a school bus carrying them hit a road divider and turned turtle near Lonavala, police said.
A female teacher accompanying the students and the driver of the vehicle also suffered critical injuries, they said.
According to officials, the children were returning after a picnic at Kolhapur when their bus hit a road divider and overturned near Amrutanjan bridge, between Lonavala and Khandala.
44 children, all students of class IV and V of the Universal School at Thane, were injured in the mishap, along with the teacher and the driver, police said.
The injured have been admitted to hospitals at Nigadi and Khopoli.
The police have asked family members of the injured to contact them on the following helplines: 9011280777 and 9823426703.