Maoists on Wednesday opened fire at a CRPF camp at Bishnugarh near Hazaribagh, which left one jawan injured, police said.
Three motorbike-borne Maoists reached the 22nd Battalion camp at Bishnugarh, about 45 km from here, at around 4 am and fired on the gates injuring a guard, DSP (Headquarters) Hazaribagh, Naushad Alam, said.
The CRPF personnel immediately took positions and returned the fire. The exchange of fire continued for about 20 minutes, Alam said, adding the ultras fled to the nearby forest.
The injured jawan, Mukesh Kumar, was referred to the Apollo Hospital at Ranchi.
The CRPF men fired 50 rounds as against 22 rounds by the Maoists, he said.
During the search, security forces spotted a blood soaked towel, indicating bullets might have hit the Maoists, the officer said.