Maoists on Thursday blew up a police jeep, killing a policeman and injuring four others at Jaranga village in Jharkhand's Khunti district.
Inspector-General of Police V Deshmukh said the jeep overturned under the impact of the blast. He ruled out the possibility of a landmine causing the blast. All the injured victims have been admitted to a hospital in Ranchi.
The Maoists also blew up a middle school, Anant Madhya Vidyala, at Pratappur in Chatra district on Wednesday night after placing dynamite in the rooms.
The school was scheduled to be one of the polling booths on December 18 for the assembly polls, the police said.
This is the fourth school in three days which has been blown up by Maoists in Jharkhand. On Tuesday, Maoists demolished two schools in Palamau district and one in Giridih district.