(CNN) Critics have accused India's ruling party of promoting communal tensions after a top official promised to rid the country of all "infiltrators" in an apparent swipe at Muslims and other religious minorities.

"We will remove every single infiltrator from the country, except Buddha, Hindus and Sikhs," Bharatiya Janata Party (BJP) president Amit Shah told supporters in West Bengal on Thursday.

We will ensure implementation of NRC in the entire country. We will remove every single infiltrator from the country, except Buddha, Hindus and Sikhs: Shri @AmitShah #NaMoForNewIndia

He promised to do so by implementing the National Registry of Citizens nationwide. The NRC is a hugely controversial policy mooted last year in Assam , a region of India which shares a porous border with Bangladesh.

Proponents of the registry say it will help root out illegal Bangladeshi immigrants, but the move has prompted fears of possible deportation among Assam's hundreds of thousands of Bengali-speaking Muslims, with an estimated 4 million people's citizenship at risk.

Implementation of the registry has been long delayed, but Shah's comments have put the issue front and center in the country's weeks-long general election, which kicked off on Thursday

In his speech, Shah said the government "won't send the Hindus, Jains, Sikhs, Parsis, Christians and Buddhists coming in from Bangladesh or Pakistan because they are our brothers and they've come here because they've faced persecution in those countries."

"To a refugee in West Bengal, I want to say, you don't have to be afraid of anyone. We treat a refugee here as a son and daughter of India and they will be given citizenship," he added. "The BJP's pledge is to get rid of the infiltrators."

Anti-Islam rhetoric

A Hindu nationalist party, the BJP has long faced accusations of anti-Muslim rhetoric.

As chief minister of Gujarat, Modi faced local and international criticism for violent rioting along communal lines in 2002 in which more 1,000 people were killed, most of them Muslims. He has never faced charges in connection with violence.

And since he became Prime Minister in 2014, critics have pointed to a rise in high-profile anti-Muslim rhetoric

The BJP and its supporters have also sought to label their critics as "anti-nationals" -- effectively, as anti-Indian -- or as in league with Pakistan, the country's main geopolitical foe.

A spokesman for the BJP did not respond to a request for comment Friday.

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Shocked and appalled

Shah's comments came in for widespread criticism Thursday.

Tony Joseph, a journalist and author of "Early Indians," said the BJP was the "true inheritor of Nazism."

"Since the ruling party is campaigning purely on hate (and) vitriol, the results of 2019 will show clearly how much of the 2014 votes it received was on account of bigotry (and) how much on account of people being taken in by its promise of 'development, development, development'," he added in a later tweet.

Model and actress Gauhar Khan said she was "shocked at how blatantly divisive" the BJP's statement was.

Amit Shah's insinuation, that Muslims shall not and cannot be safe and secure in India, will be widely acclaimed in one country: Pakistan. Shah's majoritarian bigotry is music to the ears of those who rule that country. — Ramachandra Guha (@Ram_Guha) April 11, 2019

Historian Ramachandra Guha said Shah's words would be warmly received by some in India's neighboring country, however.

"Amit Shah's insinuation, that Muslims shall not and cannot be safe and secure in India, will be widely acclaimed in one country: Pakistan," he said . "Shah's majoritarian bigotry is music to the ears of those who rule that country."

BJP's political rivals also weighed in. Preeti Sharma Menon, spokeswoman for the Aam Aadmi Party, accused the BJP and Shah of "threatening large scale persecution, or maybe they will resort to their favorite method -- genocide?"

"You may have all departments dancing to your tunes now, but soon India will respond back to this threat," she added.

This is the "new India" they want, one completely devoid of unity & brotherhood. The BJP has made it clear that they have no respect for our Constitution & no remorse in dividing our nation on communal lines.

It is the responsibility of every Indian to vote out this hatred. https://t.co/otQr1qp6yL — Congress (@INCIndia) April 11, 2019