India has brought charges of culpable homicide not amounting to murder against the chief of the country's Tableeghi Jamaat for holding a gathering last month that authorities say led to a big jump in coronavirus infections, police said on Thursday.

The headquarters of the Tableeghi Jamaat group in a cramped corner of Delhi were sealed and thousands of followers, including some from Indonesia, Malaysia and Bangladesh, were taken into quarantine after it emerged they had attended meetings there in mid-March.

Police initially filed a case against Muhammad Saad Kandhalvi, the chief of the centre, for violating a ban on big gatherings but had now invoked the law against culpable homicide, a police spokesman said.

Delhi police had filed a first information report earlier against the Tableeghi chief, "now Section 304 has been added", the officer said, referring to culpable homicide in the penal code, which carries a maximum punishment of a 10-year prison term.

A spokesman for the Tableeghi Jamaat group, Mujeebur Rehman, declined to comment saying they had not confirmed reports about the new charges.

The Tableeghi Jamaat is one of the world's biggest Sunni Muslim proselytising organisations with followers in more than 80 countries.

Authorities said at the beginning of the month that a third of the nearly 3,000 coronavirus cases at that time were either people who attended the Tableeghi gathering or those who were later exposed to them.

India's tally of coronavirus infections has since jumped to 12,380, including 414 deaths, as of Thursday.

In the coronavirus hot spot of Delhi, 1,080 of its 1,561 cases were linked to the group's gathering, according to the city government data on Wednesday.

The Tableeghi administrators earlier said many of the followers who had visited its offices in a narrow, winding lane in Delhi's historic Nizamuddin quarter were stranded after the government declared a three-week lockdown, and the centre had to offer them shelter.

Critics of Prime Minister Narendra Modi's government have cautioned against fanning communal tension by laying the blame for the spread of the coronavirus on the Muslim group.

Officials have rejected suggestions they were unfairly targeting the Muslim community, but said they had to rebuke the group because it had behaved irresponsibly by ignoring social-distancing rules.

The Tableeghi Jamaat was also linked to a surge of cases in Pakistan where it cancelled a similar gathering, but only at the last minute when thousands had already arrived at a premises in the city of Lahore.

A gathering organised by the group in Malaysia also led to a surge of cases there and in several other Southeast Asian countries.