Maoist rebels in India have released at least 250 villagers unharmed, who they were holding to stop the construction of a bridge in central India, a top police official has said.

The villagers were released late on Saturday night and have returned to their homes in Sukma district of Chhattisgarh state, said RK Vij on Sunday.

AFP news agency reported that one hostage was killed, quoting the district inspector general as saying he was found guilty of encouraging others to take part in building the bridge.

The rebels had rounded them up a day earlier and held them in nearby forests as a negotiating tactic to get the Chhattisgarh government to stop the construction of a bridge.

The rebels had been protesting against the bridge, which they fear will give security forces easy access to their hideouts, according to local lawmaker Kawashi Lakma.

The incident was considered embarrassing to the state government as it occurred on the eve of Prime Minister Narendra Modi's visit to the central Indian state.

Police said it was unrelated to Modi's visit and the seizure of the villagers was meant to stop them from working at the bridge construction site.

The government has been trying to improve road connectivity in the dense jungles of Chhattisgarh because the poor roads hinder security forces from going after the rebels.

The rebels say they are fighting for the rights of tribal people and landless farmers. They draw recruits from tribal communities who are often desperately poor and living in underdeveloped areas neglected by successive governments.

They have been called India's biggest internal security threat, operate in 20 of India's 28 states and have thousands of fighters, according to the Home Ministry.

Their fight has cost thousands of lives including through bombings and attacks on police and soldiers.

Critics believe attempts to end the revolt through security offensives are doomed to fail, saying the real solution is better governance and development.

Source: Agencies