The Union home ministry on Thursday blacklisted 960 foreign nationals linked to the Tablighi Jamaat, now at the centre of a controversy over a March 13-15 religious congregation at its southeast Delhi headquarters in Nizamuddin.

“The home ministry has blacklisted 960 foreigners, who visited India on tourist visas, for their involvement in Tablighi Jamaat activities,” a ministry official said.

“The ministry has also directed police chiefs of all states and Union Territories concerned, and the commissioner, Delhi police, to take necessary legal action against all such violators, on priority, under relevant sections of the Foreigners Act, 1946, and the Disaster Management Act, 2005.”

The gathering in Nizamuddin had around 2,000 Jamaat workers, of whom 250 were foreigners who are still in Delhi. The remaining 700-odd blacklisted foreigners are said to have left Delhi for other states or gone back to their countries.

So far, 1,804 people linked to the meet have been quarantined in Delhi and 334 with Covid-19 symptoms hospitalised.

The ministry said a search has been launched to trace others who may have come into contact with those who had attended the congregation that has emerged as the centre of a cluster outbreak.

Delhi police had on Tuesday registered a case against Maulana Md Saad, who heads the Markaz, the headquarters of the Tablighi Jamaat, and others for organising the meet in violation of government restrictions on gatherings. The move came a day after the Telangana government said six people from the state who attended the meet had died of coronavirus infection.

The Markaz has denied any wrongdoing. It has issued a statement saying it had informed Delhi police and officials of the Arvind Kejriwal government about the three-day meet.

Maulana Saad has said he had last week requested the Delhi government and Delhi police, who report to the Centre, to make arrangements for the participants to return to where they had come from but was turned down.

Navaid Hameed, president of the India Majlis-e-Mushawarat, an umbrella body of Muslim organisations, blamed the government, asking why had it issued visas to the foreigners to attend the event. “Why did officials not subject the foreigners to any medical check-up and quarantine them at the airport. It’s a big failure on the part of the government,” he said. “Why did they not ask them to disperse on March 13 itself?”

The government, he said, was shifting the blame on a particular community to divert attention from the humanitarian crisis unfolding across the country.