Thursday's polling was the first of five phases in which a total of about 714 million people - more than twice the population of the United States - will be eligible to cast ballots.

The first phase included central and eastern states battered by attacks by Maoist militants, leading to the deployment of tens of thousands of soldiers and police.

Early Thursday, suspected rebels opened fire on paramilitary soldiers patrolling in the eastern state of Jharkhand, killing six troops, police said.

Reinforcements were sent to secure the area in Latehar, about 80 miles (130 kilometres) northwest of Ranchi, the state capital, superintendent of police Hemant Topo said.

In the neighbouring state of Bihar suspected rebels attacked a polling station in Gaya district, killing a policeman, the area's Deputy Inspector General Anupama Nilokar said.

The guerrillas, known as Naxalites, have fought the government for decades in a handful of rural regions, charging authorities with plundering natural resources while providing little to local residents. Since Saturday, nearly 20 police officers have died in their attacks.

Thousands of troops were also patrolling the northern state of Uttar Pradesh, which has the most seats in the national Parliament.

Sixteen of its 80 seats were up for grabs Thursday. Three out of 14 districts in the insurgency-hit northeastern state of Assam also started voting on Thursday.

'I am aware of threat by militants but one can't stay at home out of fear,' said Monalisa Bordoloi Chakravarty. The 30-year-old homemaker was among hundreds of people who lined up amid tight security at a polling station set up in a school in Diphu, headquarters of the rebel-infested Karbi Anglong district, 215 miles (350 kilometres) south of the state capital, Gauhati. -- AP

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