Police in Pakistan tightened security on Friday as minority Shias buried a leading cleric killed in a suspected sectarian attack.
Curfews are in place in Gilgit and nearby Skardu
Agha Ziauddin died on Thursday, five days after he was gunned down in the northern city of Gilgit. Fifteen people died in violence that followed.
On Friday hundreds of Shias were held in protests in Islamabad and Lahore.
Pakistan has a long history of sectarian violence between majority Sunni and minority Shia Muslims.
The body of Agha Ziauddin was flown on Friday by helicopter from Rawalpindi, where he died of his wounds, to Gilgit, where he was buried late in the day.
Muslim tradition requires burial within 24 hours. A flight on Thursday was cancelled because of bad weather.
Curfews are in place in Gilgit and nearby Skardu. Troops have also been sent to the towns of Chilas and Nagar for a period of mourning called by Shia leaders.
Security was also tight in the southern port of Karachi - a flashpoint for many sectarian attacks - and in Islamabad.
Police in the capital fired tear gas and used batons to break up a protest by about 300 Shias on Friday.
There were hundreds of arrests there and in Lahore, where cars were destroyed and journalists attacked.
Interior Minister Aftab Ahmed Khan Sherpao has said one of Ziauddin's attackers was killed and five people have been arrested since Saturday's attack.
The authorities said only close family would be allowed at Friday's funeral.
However, Gilgit residents said about 1,500 people had tried to gather at the city's Shia mosque.
Appeal for calm
Doctors battled for three days at Rawalpindi's military hospital to save Ziauddin, carrying out operations to remove bullets from his head and neck.
Shia protesters in Lahore vent their anger at the killing
But he succumbed to his injuries early on Thursday.
As news of his death reached his hometown, hundreds of Shia protesters took to the streets in Skardu and other towns.
The Northern Areas Minister, Faisal Saleh Hayat, appealed for calm.
In recent years Pakistan has seen spiralling violence between Sunni and Shia groups. More than 4,000 people have died in the fighting since 1980.
Ziauddin had led a campaign for the past few years to have a separate Shia curriculum introduced for his community.
He was travelling by car to a mosque in the centre of Gilgit when the attack took place. He was shot twice.
Ziauddin's two armed guards were also killed in the shoot-out.
The BBC's Zaffar Abbas says that sectarian violence in the Northern Areas is often exacerbated because Shias and Sunnis are divided along tribal lines as well.
On Friday, the US embassy warned its citizens to avoid religious gatherings.
"All American citizens should avoid all mosques and areas where religious demonstrations are known to occur," the warning said.