SHEIKH SAALIQ NEW DELHI — Journalists and press freedom groups have accused Indian police of obstructing reporters covering youth protests in New Delhi over the weekend, saying dozens were detained and assaulted while doing their jobs.

Several press freedom groups said more than thirty journalists were temporarily detained during the police crackdown , which came as authorities sought to prevent mostly young Indians from gathering to protest a controversial revision of voter lists. They said the police action raised concerns about press freedom in India.

“These incidents are deeply troubling and a blot on India’s democratic traditions,” the Committee to Protect Journalists group said. It urged Indian authorities to protect journalists and hold officers accountable.

Delhi Police said some protesters had posed as journalists and interfered with police work. But police were seen dragging away and detaining journalists covering the demonstrations, including several wearing press credentials.

Lawyers later approached India’s Supreme Court on Sunday, seeking protection for journalists carrying out their duties. The court ruled in their favor.

Protests have intensified over the ongoing voter list revision, which has removed more than 130 million names from electoral rolls since last year. Critics say the exercise is politically motivated and could disenfranchise millions more. Protesters, including opposition parties, demand the resignation of Chief Election Commissioner Gyanesh Kumar.

The Election Commission and Prime Minister Narendra Modi’s administration say the revision is intended to remove duplicate and ineligible entries.

Ryan Thomas, a 26-year-old journalist with The Caravan magazine, said police beat him and briefly detained him while he covered Saturday’s demonstrations.

He said he was following protesters to document their detentions when officers surrounded him and dragged him onto a bus, despite him wearing his press card. Officers hit him on the head, neck and shoulder, tried to take his camera and ordered him to delete his video footage, he said.

Jahnavi Sen, managing editor of The Wire news website, said she was briefly detained with two colleagues. They were released after other reporters gathered and began photographing the incident, she said.

Sen said the number of journalists detained was unusual, even as pressure on the press under Modi has become more common. She said police appeared determined to stop images of their response to the protests from spreading.

“It was not that they couldn’t see” the press cards, she said. “It was because they didn’t want those visuals (of protests) going out.”

The Press Club of India, the country’s largest journalist group, called the police behavior “a blatant attack on the freedom of press.”India ranks 157th out of 180 countries in the press freedom index published by Reporters Without Borders, down from 133rd a decade ago. Critics blame the decline on Modi’s government, which has been in power for 12 years, saying it has increasingly restricted critical reporting and dissent. The government has repeatedly denied the allegations.