US Marines opened fire on demonstrators during the storming of the Karachi consulate over the weekend, two US officials said on Monday—a rare use ​of force at a diplomatic post that could sharply escalate tensions in the country ‌amid widespread protests over the killing of Iran’s leader.

Ten people were killed on Sunday when protesters breached the compound’s outer wall after Iranian Supreme Leader Ayatollah Ali Khamenei was killed in strikes on Iran.

Citing initial information, the ​two US officials said it was unclear whether rounds fired by Marines struck or ​killed anyone. They also did not know whether shots were also fired by others protecting ⁠the mission, including private security guards and local police.

This would mark the first confirmation by US ​officials that Marines were involved in firing at the protestors.

A provincial government spokesman, Sukhdev Assardas Hemnani, ​said “security” personnel had opened fire, without specifying their affiliation.

Daily security operations at US diplomatic missions are often carried out by private contractors and local forces, and the involvement of Marines in the incident underscores how seriously the ​consulate viewed the threat.

Pakistan is home to the world’s second‑largest Shi’ite community after Iran. On Monday, ​Pakistan banned large gatherings nationwide after the protests over the strikes on Iran spread, with 26 people reported dead ‌across ⁠the country.

Protesters on Sunday chanted “Death to America! Death to Israel!” outside the consulate, where Reuters reporters heard gunfire and saw tear gas fired in surrounding streets.

Video on social media appeared to show at least one protester firing a weapon toward the consulate and bloodied demonstrators fleeing as shots rang ​out.

A Karachi police official ​told Reuters that the ⁠shots were fired from inside the consulate premises.

The US Marines referred questions to the US military, which in turn referred questions to the State ​Department. The State Department did not respond to a request for comment.

Shi’ite ​community leaders have ⁠called for more protests in Lahore and Karachi despite the nationwide ban on public gatherings.

The US embassy in Pakistan is in the capital, Islamabad, and there are two additional consulates in Peshawar and Lahore.

Roads ⁠leading ​to the US consulate in Karachi were blocked off with ​a heavy police presence in the area. Similar measures were in place around US missions in Lahore and Islamabad.