Pakistan has announced plans to expel India's top diplomat and suspend trade with its neighbour, deepening a row between the countries over the disputed territory of Kashmir. Indian-administered Kashmir has been on lockdown since the Indian government decided on Monday to strip the region of its special constitutional status. Phone networks and the internet have been cut off since Sunday evening. Tens of thousands of troops have been patrolling the streets. Instances of protest and stone-throwing have been reported, despite the communications blackout and a curfew. Kashmiris in other parts of the country said that they were unable to get through to their families. Local leaders have also been detained. India and Pakistan - both nuclear-armed states - have fought two wars over Kashmir, most recently clashing in a series of aerial attacks over the territory in February. Why is Kashmir so contentious?The Himalayan region of Kashmir is claimed in its entirety by both India and Pakistan, but they each control only parts of it. There is a long-running separatist insurgency on the Indian side, which has led to thousands of deaths over three decades. India accuses Pakistan of supporting insurgents but its neighbour denies this, saying it only gives moral and diplomatic support to Kashmiris who want self-determination. Under Article 370 of the Indian constitution, the state of Jammu and Kashmir had special dispensation to make its own laws - the basis for its complex relationship with India for some 70 years. However, the Indian government is now revoking most of Article 370.