India's Election Commission said the turnout on Sunday - the first of five days of voting - was 55%, which is lower than in previous general elections. But he added that final figures will not be known for some time.

Sporadic incidents of violence were also reported, in the troubled Kashmir Valley, Punjab and the southern state of Andhra Pradesh.

The elections are staggered over a month because of the sheer scale of the exercise.

Weary electorate

The BBC's Daniel Lak says that although a high turnout is traditional in Indian elections, people may have become weary of voting after three elections in as many years.

The BBC's Mike Wooldridge has the latest on the elections

But in the southern Indian constituency of Bellary, from where Congress party leader Sonia Gandhi is locked in a high profile battle, voter turnout was reported at 60%.

A BBC correspondent says women outnumbered men in the sprawling rural constituency.

Mrs Gandhi faces a tough challenge from the BJP's Sushma Swaraj, one of the party's most prominent women politicians.

Scattered violence

In general, the vote has been peaceful, although there have been reports of sporadic violence.

Daniel Lak in Delhi: "A relative lack of interest in voting"

Police in Andhra Pradesh say a worker of the governing Telugu Desam party was stabbed to death and more than ten others injured in several clashes between supporters of rival political parties.

Police said they suspect some workers of the Congress party to be behind the incident.

Clashes between rival party activists are also being reported from the northern state of Punjab, where police said four people were wounded in gun fights.

In the troubled Kashmir Valley, voting was very low at 15%, although Kargil and Ladakh reported a higher turnout.

In the capital Delhi, press photographers crowded around as Congress leader Sonia Gandhi arrived to cast her ballot.

She looked upbeat and sounded confident as she voted, telling reporters that she was not worried about opinion polls that give her opponents a clear lead.

Mammoth undertaking

In total, 605 million people are allowed to vote - more than the combined populations of Russia, the United States and Japan.

Some 4.5 million civil servants have been requisitioned to man 800,000 polling booths, protected by almost a million police and paramilitary personnel.

In the cities, electronic voting machines are increasingly used. The rest of the country uses ballot papers, often the size of pillow cases.

As many as 60 candidates may be listed on each voting slip, alongside pictorial symbols for those who cannot read or write - just under half of the electorate.

Quiet campaign

The run up to the poll was marked by a lacklustre campaign, with personal attacks taking precedence over substantive election issues.

Police check voter registration cards

Liquor sales were banned 24 hours before polling and on election day, because of a fear that parties will use alcohol to "buy" votes.

Flamboyant campaigns gave way to more low-key, but often hi-tech, efforts.

Several candidates set up personal home pages in the hope of appealing to India's growing cyber audience.

Most recent opinion polls give Mr Vajpayee a good chance of retaining his post with a larger majority.