Seventy-nine Maoist rebels surrendered in the central Indian state of Chhattisgarh on Wednesday evening saying they had lost faith in their comrades' ideology, police said.
Among them were 29 who had been involved in violent confrontations with state troops, police said.
"With the mass surrender, our drive to curb the leftist insurgency movement in the state will receive a big boost," O.P. Rathod, a top state police official, said by phone from Raipur, the state capital.
The rebels were driven by police from the trouble-torn Bastar region to police headquarters in Raipur, where they laid down five weapons in front of the chief minister, Raman Singh.
Hundreds of people have been killed and 50,000 left homeless in Chhattisgarh, one of the worst-hit among 13 states affected by Maoist violence.
Last week, security forces shot dead a senior Maoist leader in Andhra Pradesh in what police said was a big blow to the leftist insurgents.
The Maoists say they are fighting for the rights of millions of India's poor labourers and landless peasants in an insurgency that has killed thousands of people in India.
Decades of neglect have allowed the Maoists - known as Naxalites after the West Bengal town of Naxalbari where the movement began in 1967 - to develop deep roots in most of India's poorest states.