Farooq Abdullah had been confined to his residence in the main city of Srinagar since August 5 when the Indian government split the Muslim majority state and put it under direct New Delhi rule.
Indian authorities on Friday ordered the release of Kashmir's most prominent politician Farooq Abdullah, one of dozens of leaders held since August, when the federal government scrapped the disputed region's autonomy.
Prime Minister Narendra Modi's government said at the time that ending Kashmir’s special status was necessary for closer integration of the Muslim majority territory into the rest of India.
The government imposed a communication blackout with mobiles phones, internet links and landlines down and the detentions of scores of people including Abdullah to prevent large scale protests from erupting over the loss of autonomy for Kashmir.
The federal government said those measures were necessary to stop separatists and militants from stirring trouble. The government did not offer any reason on Friday for Abdullah's release when it made the announcement.
Abdullah, a former chief minister, told reporters he was happy to be free, but there were many others still under detention including his son and also a former chief minister Omar.
"But this freedom is not complete; the freedom will be complete when all the leaders .... who are in either prisons in the state or outside the state, on in ... hostels or in various buildings where they have been put under house arrest," he told reporters in main city Srinagar.
Abdullah said a window had opened with his release.
"I hope that the government of India takes action soon to release everyone if they want that the people of the state should have freedom to live as free people," he said.
New Delhi locked down the region following the August move, bringing in tens of thousands of troops into the already heavily militarised territory.
Restricted Internet access was allowed in late January after a blackout lasting almost six months.
The security lockdown and detentions have drawn international criticism including by the European Union and the United States.
Kashmir has been divided between India and Pakistan since the partition of the subcontinent in 1947. They have fought two of their three wars over control of the territory.
Rebel groups have fought for decades for the Himalayan region's independence or its merger with Pakistan.
The fighting has left tens of thousands dead since 1989, mostly civilians. India has more than 500,000 troops in Kashmir.