AFP - Indian Maoists killed at least 22 policemen, including a senior officer, in an ambush Sunday in the eastern state of Chhattisgarh, officials said.
  
The attack took place in Rajnandangaon district, 90 kilometres (56 miles)  from the state capital Raipur, Pawan Dev, deputy inspector general of police in charge of operations against the left-wing rebels, told AFP.
  
The guerrillas shot dead two policemen on patrol in the area and then ambushed the security team that was sent to investigate the incident, he said.
  
"We have information of 22 policemen killed in the attack," Dev said.
  
A state government spokesman said superintendent of police V.K. Choubey was among those killed.
  
Sunday's attack comes a month after 11 special police personnel were killed in a landmine blast triggered by Maoists in Chhattisgarh, where the left-wing rebels are based.
  
In April the rebels took more than 300 passengers hostage in an audacious attack in the neighbouring state of Jharkhand.
  
India's Maoists say they are fighting for the rights of neglected tribal people and landless farmers. They are now active in more than half of the country's 29 states -- particularly in the east, the poorest part of India.
  
The insurgency grew out of a peasant uprising in 1967.
  
Prime Minister Manmohan Singh has described the rebellion as the single largest threat to India's security.