Raipur, March 18 (IANS) Two Central Reserve Police Force (CRPF) troopers were killed and three others were injured in a blast Maoist insurgents triggered Thursday in a thickly forested area in Chhattisgarh.

'CRPF head constable B. Haribhai was killed on the spot while a constable Balbir Singh succumbed to injuries later at the hospital when Maoist militants attacked a CRPF contingent with an improvised explosive device (IED),' Bijapur Superintendent of Police Avinash Mohanty told IANS.

He said the dead, who belonged to CRPF's 168th battalion of the CRPF, were on a road opening assignment when Maoists triggered the blast.

Three CRPF men who sustained injuries in the attack were airlifted to Jagdalpur town, district headquarters of Bastar, where they were admitted to a government hospital. Doctors have termed their condition as critical.

Mohanty said rebels targeted the troopers when they were passing through Awapalli-Basaguda road, about 500 km south of the state capital Raipur. Extra troopers have been sent in the blast site area for apprehending the attackers.

Bijapur along with Bastar, Dantewada, Narayanpur and Kanker comprise the 40,000 sq km Bastar region where Maoists have been running a parallel government since the late 1980s.

About 1,600 people have been killed since 2005 in Chhattisgarh in Maoist violence; of these, 90 percent casualties were reported from Bastar region, officials at the police headquarters here said.