A senior police officer in an Indian state which has seen 19 deaths in protests over a controversial citizenship law has been filmed telling demonstrators to “go to Pakistan”.

Critics have claimed a new law which makes it easier for members of persecuted religious minorities, but not Muslims, to become eligible for citizenship is discriminatory and violates India's secular constitution.

Uttar Pradesh (UP), the country’s most populous state with nearly 20 per cent of its population Muslim, has seen the majority of at least 25 deaths so far during the protests.

Akhilesh Narayan Singh, a senior UP police officer, was filmed telling protesters to “go to Pakistan if you don't want to live here” in a video which has been widely-circulated on social media.

The video is likely to compound concerns that Muslims are being marginalised under Narendra Modi’s Hindu nationalist government.

Indian General Election 2019 Show all 10 1 /10 Indian General Election 2019 Indian General Election 2019 Bharatiya Janata Party (BJP) President Amit Shah (R) welcomes Indian Prime Minister Narendra Modi (L) at BJP headquarters prior to a ceremony to thank the Union council of Ministers for their contribution in India's general election, in New Delhi on May 21, 2019 AFP/Getty Indian General Election 2019 An Indian Bharatiya Janata Party (BJP) supporter shouts slogans and holds the party flag as he celebrates on the vote results day for India's general election in New Delhi on May 23, 2019. - Prime Minister Narendra Modi looked on course on May 23 for a major victory in India's election, with early trends from the election commission showing a clear lead for his party. AFP/Getty Images Indian General Election 2019 Indian election officials count votes using electronic voting machines at a counting center for the Lok Sabha (lower house of Parliament) election, in Jammu, the winter capital of Kashmir, India, 23 May 2019. The parliamentary elections, which began on 11 April 2019, were held in seven phases throughout India and are currently being tabulated. The Lok Sabha elections were held for 542 of the 543 Lok Sabha seats, and a party or alliance needs 272 seats to form a government. EPA Indian General Election 2019 Indian supporters of Bharatiya Janata Party (BJP) dance as they celebrate on the vote results day for India's general election in Siliguri on May 23, 2019. - Prime Minister Narendra Modi looked on course on May 23 for a major victory in India's election, with early trends from the election commission showing a clear lead for his party. AFP/Getty Images Indian General Election 2019 Indian supporters and party workers of Bharatiya Janata Party (BJP) dance as they celebrate on the vote results day for India's general election in Bangalore on May 23, 2019. - Indian Prime Minister Narendra Modi looked on course on May 23 for a major victory in the world's biggest election, with early trends suggesting his Hindu nationalist party will win a bigger majority even than 2014. AFP/Getty Images Indian General Election 2019 Indian supporters and party workers of Bharatiya Janata Party (BJP) dance and hold flags as they celebrate on the vote results day for India's general election in Bangalore on May 23, 2019. - Indian Prime Minister Narendra Modi looked on course on May 23 for a major victory in the world's biggest election, with early trends suggesting his Hindu nationalist party will win a bigger majority even than 2014. AFP/Getty Images Indian General Election 2019 An Indian member of the Dravida Munnetra Kazhagam (DMK) shouts slogans and shows portraits of party president M.K. Stalin as she celebrates on the vote results day for India's general election in Chennai on May 23, 2019. - Indian Prime Minister Narendra Modi looked on course on May 23 for a major victory in the world's biggest election, with early trends suggesting his Hindu nationalist party will win a bigger majority even than 2014. AFP/Getty Images Indian General Election 2019 Bharatiya Janata Party (BJP) supporters, wearing masks dipicting Indian Prime Minister Narendra Modi, celebrate BJP's potential win in the the Lok Sabha election the Lok Sabha elections, in Amritsar, India, 23 May 2019. The Lok Sabha, the lower house of Parliament, elections, which began on 11 April 2019, is having the results tallied today. The Lok Sabha elections were held for 542 of the 543 lower house seats, and a party or alliance needs 272 seats to form a government. According to initial polling Narendra Modi could retain the position of Prime Minister along with the Bhartya Janta Party. EPA Indian General Election 2019 A Bharatiya Janata Party (BJP) supporter wears a mask dipicting Indian Prime Minister Narendra Modi as he celebrates BJP's potential win in the the Lok Sabha election the Lok Sabha elections, in Amritsar, India, 23 May 2019. The Lok Sabha, the lower house of Parliament, elections, which began on 11 April 2019, is having the results tallied today. The Lok Sabha elections were held for 542 of the 543 lower house seats, and a party or alliance needs 272 seats to form a government. According to initial polling Narendra Modi could retain the position of Prime Minister along with the Bhartya Janta Party EPA Indian General Election 2019 Bharatiya Janata Party (BJP) supporters celebrate in their party's Assam state office in Gauhati, India, Thursday, May 23, 2019. Indian Prime Minister Narendra Modi and his party have a commanding lead in early vote counting from the country's six-week general election. AP

Mr Singh later told Reuters his comments were a response to some protesters who had been shouting pro-Pakistan slogans.

“It is in this situation I told them to go to Pakistan,” he said on Saturday.

The controversy over the video came as the UP chief minister, Yogi Adityanath, rebuffed accusations from rights groups of police abuses during protests against the Citizenship Amendment Act (CAA).

Mr Adityanath, a hardline Hindu priest who belongs to Mr Modi’s Bharatiya Janata Party, has claimed his tough policies have restored calm to the state.

“Every rioter is shocked. Every troublemaker is astonished. Looking at the strictness of the Yogi government, everyone is silent,” he wrote on one of his official Twitter accounts.

“Do whatever you want to, but the damages will be paid by those who cause damages.”

Last week, the UP government said it was demanding millions of rupees from more than 200 people and threatened to confiscate demonstrators' property to pay for damages during protests.

Rights groups have accused the state government of “employing unlawful and lethal tactics” against protesters and decried what they say have been mass detentions in UP, where officers have arrested more than 1,000 people.

The CAA allows Hindus, Christians and other religious minorities to become citizens in India if they can show they were persecuted because of their religion in neighbouring Muslim-majority countries - Afghanistan, Bangladesh and Pakistan.

However, the law does not offer concessions to Muslims.

Officials from the opposition Congress party were set to lead protests on Saturday under the slogan "Save Constitution-Save India".

“They can punish us, throw us in jail, siphon our property but they will not be able to stop us from continuing our protest,” said Akhilesh Tomar, a student activist who is working with the Congress to coordinate protests in four Muslim-dominated districts of UP.

Protests were also planned in the northeastern state of Assam, where migration has long been an emotive political issue.

Meanwhile, Hindu activists associated with Mr Modi's party were conducting workshops in slums in an effort to ease public discontent.

“We have to explain the facts to the common people who are being misled against the law by the opposition,” said Ram Naresh Tanwar, a member of a group called the Hindu Jagran Samiti, or Hindu awareness committee, in New Delhi.