A senior Indian official says left-wing extremism is the “most violent movement” in the country.

Home Minister P. Chidambaram says the government plans to increase security personnel to combat the violence carried out by Naxalite, or Maoist, insurgent groups.

He spoke Tuesday in New Delhi to officials from more than 60 districts affected by violent attacks by Naxalites.

India's Prime Minister Manmohan Singh has referred to Naxalism as the top security threat facing his country. The groups include some of India's extreme poor, who say they are struggling against state-sanctioned acquisition of their land and natural resources.

Naxalites are widely considered terrorists. Thousands of civilian and police deaths in India have been blamed on Naxalite attacks since the rebel groups emerged in the late 1960s.