BANIHAL : Indian Prime Minister Manmohan Singh opened Wednesday the country's longest railway tunnel during a rare visit to troubled Indian-occupied Kashmir, which has been marred by one of the deadliest freedom fighters attacks on soldiers in years. Singh inaugurated a stretch of line that runs through the 11-kilometre long tunnel, part of an ambitious multi-year railway project in the region, as he wrapped up his first visit to the region in three years. "It took seven years to complete," Singh said of this section of the project, during a speech in the town of Banihal, some 110 kilometres from the main city of Sriningar.

It is the first time the premier has visited the Indian Held part of the divided Himalayan territory -- which has been the scene of two wars with Pakistan -- since June 2010 and comes less than a year before India goes to the polls.

The tunnel and railway stretch have been added to a train line running through the valley, part of a 20-billion-rupee ($470-million dollar) project that will eventually link Kashmir to the rest of India's vast railway network.

Sections of the track have been drilled through the Himalayan mountains, and Singh said it was a "national dream" to link Kashmir with the network by 2018.

Singh faced protests when he arrived in Kashmir on Tuesday after the region's three main separatist groups called a strike against his visit.

Shops and other businesses, along with schools, banks and offices were closed throughout Srinagar and security forces were deployed in strength.

More than a dozen armed rebel groups have been fighting Indian forces since 1989 for the region's independence or its merger with Pakistan and tens of thousands of people, mostly civilians have died in the fighting.

Armed violence had been declining steadily since the early 2000s but the region has been tense following the execution in February of a local man over a deadly 2001 attack on the national parliament in New Delhi.

Mohammed Afzal Guru's execution, carried out in a New Delhi prison without first informing his family, triggered widespread protests in Kashmir where many doubted his guilt.