The improvised explosive device (IED) blast took place around 2 pm near Pipradaba at the foothills of Budha Pahar, parts of which fall in Balrampur district of Chhattisgarh and Latehar district of Jharkhand, CRPF sources said.
Five Central Reserve Police Force (CRPF) personnel, including an assistant sub-inspector (ASI), one Jharkhand Jaguar Force constable and one Jharkhand police constable were injured in the incident, the police said, adding that all of them were airlifted to Ranchi by a helicopter.
The blast was triggered when the security personnel were carrying a jawan, who had fallen sick, to a base camp, the police said.
Following the blast, the CPI (Maoist) cadre started firing indiscriminately on the security personnel, they added.
The ultras made a hasty retreat, taking advantage of the forest cover in the area when the security personnel retaliated, the CRPF sources said.
Jharkhand Inspector General of Police (Operations) Ravi Kant Dhan confirmed the incident.
The security forces had been carrying out a massive anti-Naxal operation at Budha Pahar for the last few days, the sources said, adding that the entire area was cordoned off, in a bid to affect the supply line to the Naxals.
The security personnel have also set up camps in the area.
Those injured were: ASI R K Pandian, Atul Tamboli, Ramesh Biroly, Niwash Tete, Mukesh Kumar -- all from the CRPF -- Dilip Kumar of Jharkhand Jaguar Force and Koushal Kumar of Jharkhand police, the police said.
"As per preliminary reports, the condition of the injured troops is not critical," a senior CRPF officer said, adding that the injured personnel of the force belonged to its 62nd battalion.
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