Pakistan has deployed the military and imposed a three-day curfew in the northern cities of Gilgit and Skardu.

The deployment comes after deadly protests against the killing of Iranian Supreme Leader Ayatollah Ali Khamenei in a US-Israeli attack. At least 25 people have been killed and dozens injured across the country.

Thousands of Shiite demonstrators attacked UN offices in Skardu, in the northern Gilgit-Baltistan region, on Sunday. In the city of Gilgit, protesters burned a police station and damaged a school, officials said.

Police said at least 12 people were killed and 80 others wounded in the Gilgit-Baltistan region.

UN spokesperson Stephane Dujarric said Monday that Skardu's UN Military Observer Group Field Station, which monitors the ceasefire along the disputed region of Kashmir, was vandalized when protesters turned violent nearby. 

"The safety and security of UN personnel and premises throughout the region remain our top priority, and we continue to closely monitor the situation," Dujarric said.

Protests in Karachi and other cities

Demonstrations also erupted in the southern port city Karachi. Protesters stormed the US consulate on Sunday, smashing windows and attempting to set the building on fire. Ten people died, and more than 50 were injured in clashes with police. 

Meanwhile, one person was killed in clashes in the capital, Islamabad.

Thousands also protested in the northern cities of Parachinar, Dera Ismail Khan and Peshawar, but no clashes were reported.

Pakistan is home to the world's second-largest Shiite community after Iran. While Shiites are a minority nationwide, in some northern areas, including Gilgit-Baltistan, they constitute a majority.

Heightened security around US missions

In the wake of the weekend protests, Pakistani authorities have boosted security around US diplomatic missions across the country. Police blocked off roads leading to the consulate in Karachi, and similar measures were also in place in Lahore and Islamabad.

The embassies of the US and UK both urged citizens in Pakistan to be cautious.

The latest unrest comes amid ongoing border clashes between Pakistan and Afghanistan. The violence erupted on Thursday when Afghanistan launched attacks in retaliation for Pakistani airstrikes the previous weekend.

Edited by: Zac Crellin