Police used tear gas and pellets to fight back at least 10,000 people protesting Delhi's withdrawal of special rights for Jammu and Kashmir in its main city of Srinagar on Friday, a police official and two witnesses said.
The demonstration soon after Friday prayers was the largest since authorities locked down the revolt-torn region five days ago, cutting off telephone and internet services and detaining more than 500 political and separatist leaders.
It comes after the government scrapped Jammu and Kashmir's right to frame its own laws and allowed non-residents to buy property there.
Regional leaders have warned of a backlash in the area, where militants have been protesting for nearly 30 years, leading to the deaths of more than 50,000 people.
A large group of people gathered in Srinagar's Soura area, a police officer said, in violation of orders that prohibit the assembly of more than four people.
The crowd was pushed back by police at Aiwa bridge, where a witness said tear gas and pellets were used against them. "Some women and children even jumped into the water," a witness said at Srinagar's Sher-e-Kashmir Institute of Medical Sciences, where pellet victims were admitted.
"They (police) attacked us from two sides," another witness said. The police officer said 12 people had been admitted to two hospitals in the city after receiving pellet injuries at Soura, taking the total injured in the protests this week to at least 30.
"There were around 10,000 people at the protest in Soura," the police officer said. "This was the biggest so far."
Thousands of extra paramilitary police were deployed across Kashmir just before the sweeping measures were announced on Monday to prevent large-scale protests.
Addressing the nation on Thursday, Prime Minister Narendra Modi said he had acted in Kashmir to help develop the region and that he hoped it would lead to investment and more job opportunities.
The BJP has long campaigned for abrogating Kashmir's special privileges in the constitution, which it sees as an appeasement to Muslims and a hindrance to its own development.
MEA spokesperson Raveesh Kumar, played down the unrest, which he suggested was temporary.
"Just outside Srinagar things have really come back to normal," he said.
Kumar added, "People are going about their business, vehicles are plying normally. If we are confident of maintaining the law and order, I think those restrictions will be relaxed, I'm quite sure."
But the police officer, who requested anonymity since he is not authorised to speak to the media, said that political detentions in the wake of the Modi government's decision to revoke Kashmir's special rights were continuing.
"Over 500 people are now arrested since Sunday," he said, including former chief ministers, ministers, lawmakers and leaders and workers from political parties and separatist groups.
PM Modi's party and even some top opposition leaders have welcomed the decision to absorb Kashmir fully into India, and it has brought him support across the country.
Within Kashmir, officials are hoping anger will die down. On Friday, they eased restrictions to allow residents to offer prayers in neighbourhood mosques and said they were making arrangements for Eid, that falls on Monday.
The top administrative official of the Kashmir Valley, Baseer Khan, said that essential commodities including food, grains and meat, would be trucked into villages by Sunday.
Khan also said authorities would set up public phone booths covering every district, since communications lines have been severed by the government anticipating widespread protests.
"More than 300 phone booths will be established in a day or two at landmark points," he said.
Khan added that all medical services in the valley were working normally, although when Reuters visited two major hospitals and a smaller facility, officials said that doctors and staff were having difficulties reaching work.
On the other hand, Pakistan has downgraded diplomatic ties with India and suspended trade in anger at the Kashmir move.
On Friday, senior Chinese diplomat Wang Yi said China was gravely concerned about the situation in Kashmir, the cause of two of three wars between nuclear-armed India and Pakistan.
Wang met Pakistan's Foreign Minister Shah Mahmood Qureshi in Beijing and assured him that China would continue to support Pakistan to safeguard its legitimate rights and interests, the Chinese Foreign Ministry said in a statement.