A Pulitzer-winning photojournalist from Indian-administered Kashmir has said that she was stopped from travelling to the US by immigration authorities at Delhi airport.

Sanna Irshad Mattoo was awarded the Pulitzer for her coverage of the Covid-19 pandemic and was on her way to attend the award ceremony.

Ms Mattoo said she was stopped "despite having a valid visa and ticket".

The Indian government has not made a statement yet on why she was stopped.

News agency PTI quoted Jammu and Kashmir police officials as saying that she had been placed on a no-fly list.

Ms Mattoo said this was the second such incident in four months. The journalist told the BBC she asked officials why she hadn't been allowed to travel but was not given a reason.

She said she was "heartbroken" at not getting the chance to attend the ceremony, describing the Pulitzer as a "dream for every journalist".

Several activists and journalists have been stopped from leaving or entering the country this year.

In March, journalist Rana Ayyub - who writes for the Washington Post - was stopped at Mumbai airport when she was about to board a flight to the UK to deliver a speech at the International Centre for Journalists.

Ms Ayyub was allowed to travel a few days later after she won an appeal against the decision in the Delhi High Court and got permission.

In April, former Amnesty India chief Aakar Patel was stopped twice from boarding a flight to the US at Bangalore airport.

This followed a federal investigation into Amnesty allegedly breaking India's foreign currency exchange laws during Mr Patel's tenure as its chief. The agency called him a "flight risk". He was later asked by a court not to leave the country without its permission.

In August, Angad Singh, an Emmy-nominated American journalist of Indian-origin, was reportedly deported to New York soon after he landed in Delhi.

While the Indian government did not comment on the incident, Mr Singh's family said his passport was confiscated at the airport before he was deported. His mother alleged his treatment was a response to the documentaries the journalist had made on India's Covid crisis and farmers' protests for Vice News.

Earlier this year, the federal government deported Professor Filippo Osella, an anthropologist at the University of Sussex, who had been visiting India for more than 30 years.

Prof Osella challenged his deportation in the Delhi High Court, calling it arbitrary and unconstitutional. He also said he was treated like "a hardened criminal" by Indian authorities without being given a reason for his deportation.

Last week, the Indian government defended its decision in court, saying that the academician had been placed in the "highest category of blacklisting" based on "sufficient material" against him.