Here are 10 developments in this story:
The Maoists allegedly used villagers as human shields and fired at the soldiers, who could not retaliate.
"The Naxals were using local villagers as shields, so our troops couldn't retaliate with full force as that would also have cost villagers' lives," a senior CRPF officer was quoted as saying.
The Maoists struck deep in the forests at Sukma, 450 km from state capital Raipur, when the soldiers were returning to their base after searching for rebels.
Two officers were among those killed and a dozen soldiers were wounded in the attack, said the police.
The attack took place around nine km from Chintagufa, where 76 jawans were killed in 2008 in one of the worst Maoist attacks ever.
"It is an act of cowardice. I strongly condemn this dastardly act of violence. It is a challenge for the entire country," the Home Minister said. He is likely to visit Chhattisgarh tomorrow.
The CRPF has been searching the area for two weeks. Last month, 15 Maoists were killed in an encounter with the forces in the area.
The rebels also fired at an Indian Air Force helicopter that was evacuating wounded personnel. Five soldiers died and an IAF commando was injured.
Maoists have been called India's biggest internal security threat. They operate in 20 of India's 28 states and have thousands of fighters, according to the Home Ministry.
The rebels say they represent the poor living close to the land, including farmers and members of tribal groups who depend on forests for food, fuel and shelter.
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