Indians began voting on Thursday in the first phase of a mammoth general election, with Prime Minister Narendra Modi gunning for a second term having campaigned strongly on his national security record following a flare-up in tensions with Pakistan.

India Election 2019: Decoding the Pakistan factor

Security for the polls was increased after seven people were killed in militant attacks in Jammu and Kashmir, the country's only Muslim majority state, and in eastern India, where Maoist insurgents were blamed for a bomb that killed a state legislator from Modi's Hindu nationalist Bharatiya Janata Party (BJP).

Voting in the first of seven rounds is being held in 91 parliament constituencies across 20 states and federally administered regions. There are 543 seats at stake.

Modi's BJP has entered the election as the frontrunner, despite economic distress over mounting unemployment, and weak farm incomes in rural areas, where two-thirds of Indians live.

In a posting on Twitter as voting began, Modi urged people to turn out in large numbers and said the mood nationwide was running in favor of his alliance.

Pollsters say support for the BJP rose in response to Modi's tough stance against Pakistan, which saw aerial clashes between the nuclear-armed neighbors following a Pakistan-based militant organization's suicide attack in February that killed 40 paramilitary police in Kashmir.

The main opposition Congress party, which wrested three major farming states from the BJP in December by promising to waive the outstanding loans of distressed farmers, has looked for allies among regional parties to defeat the BJP over its record on the economy.

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(With input from Reuters)