An estimated 2.5 million people in central India were left without electricity yesterday following a Maoist guerrilla attack on power lines, police said.

Three government employees were killed and five security personnel injured in the attacks in Chhattisgarh state by the rebels, who champion the rights of tribes and farmers they say have been left behind by India's economic boom.

"Those who were killed in the blast were involved in the electricity repair work," police inspectorgeneral RK Vij told AFP in the state capital Raipur.

State chief minister Raman Singh put the cost of the power outage in the millions of dollars.