A state legislator for India's ruling Bharatiya Janata Party (BJP) and four others were killed in a roadside bomb attack carried out by Maoist militants in India on Tuesday, two days before the country is due to start voting in a national election.

Police said BJP legislator Bhima Mandavi, his driver and three of his state bodyguards were killed in a "massive" explosion in a remote part of Chhattisgarh state, some 340 kilometers (211 miles) from the state's capital, Raipur.

Chhattisgarh is a restive central state where Maoist rebels have been pursuing an armed insurgency for decades.

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"According to our preliminary investigation, five people have died," said P. Sundar Raj, the state's police deputy inspector general for anti-Maoist operations. "It was a powerful IED [improvised explosive device] blast. It left a crater on the ground."

Modi criticizes attack

Prime Minister Narendra Modi, who hails from the same party as the slain state legislator, condemned the strike.

"My tributes to the security personnel who were martyred," he posted on Twitter. "The sacrifices of these martyrs will not go in vain."

A history of political attacks

The rebels often call for a boycott of polls as part of their campaign against the Indian state, and have previously timed strikes to coincide with elections.

During the last national election in 2014, they killed seven police in a landmine attack.

The year before, 25 politicians from the Congress party were murdered in Chhattisgarh in an ambush on their convoy during regional polls.

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There are armed insurgencies in at least nine Indian states, from Kashmir in the north to the jungles in the country's interior, creating risky conditions for party officials and their candidates during campaigning.

Maoist groups are believed to be present in at least 20 other Indian states, but they are most active in a forested section of the country dubbed the "red corridor," which encompasses the states of Chhattisgarh, Odisha, Bihar, Jharkhand and Maharashtra.

The rebels say they are fighting for landless farmers, the poor and indigenous communities. They claim to have thousands of fighters and control territory in several Indian states.

law/msh (AFP, AP, Reuters)

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