At least 21 people were killed and 39 injured when the bus in which they were travelling rammed into a tree before overturning near Angara, about 35 km from Ranchi, on Wednesday.
Eyewitnesses said the bus skidded off the road when the driver was trying to save a motor-cyclist.
Superintendent of Police Suman Gupta said the bus was on its way from Purulia in West Bengal to Ranchi.
While 10 persons died on the spot, 11 succumbed at the Rajendra Insititute of Medical Sciences in Ranchi.
