Indian Prime Minister Narendra Modi on Friday filed nomination papers in a Hindu holy city, hoping to hold onto the seat for a second time in the general elections.

He prayed at a temple before arriving at the election office in Varanasi in Uttar Pradesh state, flanked by Amit Shah, president of his Hindu nationalist Bharatiya Janta Party, and several state chief ministers.

As his car passed, thousands of BJP activists, some carrying party flags and sporting saffron caps, waived at Modi who responded with a smile. People also showered rose petals on him. Many were perched on the road dividers and many more watched the show from windows and roofs of homes on both sides of the roads.

Voting in three of the seven phases of the staggered elections has finished. In total, some 900 million people are registered to vote for candidates to fill 543 seats in India's lower house of Parliament. Voting concludes on May 19 and counting is scheduled for May 23.

With around 1.7m voters, Varanasi will go the polls on May 19. The election is seen as a referendum on Modi and his party.

The campaigning has been marred by accusations, insults and unprecedented use of social media to spread false information.

Varanasi is one of the holiest cities for Hindus in India and is based at the banks of the Ganges River, or Ganga. Hindus believe Varanasi is the center of the world and anyone who dies in the city attains salvation.

Invoking Hindu symbolism, Modi told party workers before filing his nomination papers: “Mother Ganga will take care of me.”

“Last time when I contested nobody told me to come here, nobody sent me to Varanasi. Mother Ganga has invited me,” he added.

Modi supporters say the tea seller's son from Gujarat state has improved the nation's standing. But critics say his party's Hindu nationalism has aggravated religious tensions in India.

In his five years as prime minister, Modi has pushed to promote this secular nation of 1.3 billion people and nine major religions as a distinctly Hindu state.

He has rallied his support base with Hindu mega projects across India, including in Varanasi, but has also been blamed for rising attacks by Hindu mobs against minorities, mainly Muslims who number about 170m.

Modi and his party also have adopted aggressive nationalism, using the disputed Himalayan region of Kashmir to pivot away from his economic record and playing up the threat of rival Pakistan.

The approach was employed especially after a suicide bombing in Kashmir on Feb 14, that killed 40 soldiers, causing brief fighting with Pakistan and allowing Modi to portray himself as a strong, uncompromising leader on national security.