The hijack comes five days after voters in Jharkhand went to the polls as part of the first phase of national elections. The state is set for a second stage of elections on Thursday.

More than 714 million are eligible to vote in the month-long election over April and May.

Elections marred

Maoist violence disrupted the first stage of India's election last Thursday when five election officials were killed in a blast in Chhattisgarh state.

Eleven police were killed across the central and eastern "red belt".

Manmohan Singh, the Indian prime minister, has described Maoist violence as India's biggest internal security threat. About 500 civilians and police were killed last year in violence related to the Maoists.

The Maoists, who say they are fighting for the rights of landless labourers and poor farmers, have stepped up attacks in their strongholds in central and eastern India during the general election.

The Maoist rebellion, which grew out of a peasant uprising in 1967, has hit more than half of the country's 29 states.

The rebels use the forests of neighbouring Chhattisgarh as their base.