Hundreds of angry youth burnt tyres and blocked roads in the northern mountain town of Skardu on Sunday, though there were no reports of any casualties.

The government beefed up security in another town, Karimabad, where enraged crowds attacked local government offices late on Saturday night.

The violence was sparked following an attack on religious leader Ziauddin Rizvi in Gilgit, the main town in the mountainous region known as Northern Areas.

Skardu is the last major town on the way to K-2, the world's second-highest mountain, while Karimabad is the capital of scenic Hunza valley on the Karakoram Highway that goes up to China.

More casualties

Rizvi was travelling in his car to a mosque in the centre of Gilgit, 240km north of the capital Islamabad, when unidentified assailants opened fire, critically injuring Rizvi and his three guards. Two of the guards later died.

Dr Muhammad Yaqub at the government hospital in Gilgit said the death toll had risen to 14 from 11 in the violence on Saturday, after which a curfew was imposed in the town and the army was called in to control the mob.

The curfew was still in place on Sunday, and residents said soldiers were patrolling the streets on vehicles with machineguns mounted atop them. 

No one has claimed responsibility for the attack on Rizvi but police suspect it was a sectarian incident.