SRINAGAR, India — The lives of millions in the Indian-controlled portion of Kashmir have been upended since New Delhi imposed an unprecedented security lockdown and a near-total communications blackout in the divided Himalayan region.

It follows a decision by India to revoke the special status of Jammu and Kashmir and downgrade the country’s only Muslim-majority region from statehood to a territory.

Tens of thousands of government forces in riot gear now patrol the deserted streets lined with shuttered shops. Steel barricades and razor wire cut off neighborhoods. An eerie silence is broken by an occasional security vehicle whizzing past or the cawing of crows.

With landline, cellphones and internet down, Kashmiris can’t call one another or outside the region, relying only on limited cable TV and local radio reports for news.