NEW DELHI, March 12 (Xinhua) -- At least two border guards of India's Border Security Force (BSF) were killed and four others wounded Saturday in a fierce gunfight with Naxals in central state of Chhattisgarh, officials said.

The gunfight broke out in the morning at Kanker district, about 127 km south of Raipur, the capital city of Chhattisgarh.

"Two BSF constables were killed and four others wounded in a gunfight with Maoists in Kanker district this morning," an official said. "The wounded BSF men were immediately hospitalized."

India's official broadcaster - All India Radio (AIR) said the gunfight broke out when a joint team of BSF and police were on a search operation in Pakhanjoor area of the district.

"Maoists ambushed the team near Bechghat in Chote Betia area and in the ensuing gun battle six BSF men sustained bullet wounds," the state broadcaster said.

On Friday a dozen paramilitary troopers of India's Central Reserve Police Force (CRPF) were wounded after their vehicle was hit by a landmine planted by Naxals in remote Sukma district of the state.

Naxalites are also known as "Maoists".

Maoist insurgency has its genesis in the violent left-wing rebellion that began in 1967 at village Naxalbari in Indian state of West Bengal.

Currently Maoists are active in more than a third of India's 600-odd districts across central and eastern India.

India's former prime minister Manmohan Singh once termed the Naxalite movement as India's "greatest internal security challenge".

New Delhi has deployed several companies of its paramilitary forces to take on Naxals in their strongholds.

Reports say the insurgency has claimed more than 6,000 lives and rendered thousands of poor inhabitants homeless.