New Delhi - Five security personnel were killed and at least two injured in a landmine blast triggered by Maoist rebels in the eastern Indian state of Jharkhand on Saturday, news reports said.

The blast took place on a national highway in Latehar district, about 140 kilometres north-west of Jharkhand capital Ranchi, IANS news agency reported.

"Five security personnel who were on long-range patrol were killed in a landmine blast by Maoists. The dead personnel include the officer in charge of Manika police station," a local police officer was quoted as saying.

Maoist rebels are active in 18 of Jharkhand's 24 districts. At least 1,400 people including 744 civilians and 320 security personnel have been killed in Jharkhand in Maoist insurgency-related incidents since 2001.

Maoist militants, who claim to be fighting for tribal people and the rural poor, operate in 13 of India's 29 states.

Prime Minister Manmohan Singh has described the Maoist insurgency as one of the gravest internal security threats facing India. (dpa)