DUBAI (Reuters) - Gunmen in Iran shot dead a commander of the hardline Basij militia who was an ally of Qassem Soleimani, the senior Revolutionary Guards commander killed in a U.S. drone strike in Iraq, the official news agency IRNA reported on Wednesday.

The Basij are under the command of the Guards, the most powerful and heavily armed security force in the Islamic Republic.

IRNA said that Abdolhossein Mojaddami, a Basij commander in the city of Darkhovin in the southwestern province of Khuzestan, was shot on Tuesday in front of his home by two men riding a motorcycle.

There was no immediate claim of responsibility for the attack, IRNA said. It described Mojaddami as one of the “defenders of the shrine”, a reference used to describe members of security forces who have fought in recent conflicts in Iraq or Syria.

Soleimani, a general who oversaw Iran’s drive to extend its influence across the Middle East, was killed at Baghdad airport on Jan. 3, prompting Iran to fire missiles at U.S. forces in Iraq in an escalation of their confrontation over Tehran’s nuclear program and broader security issues in the region.

On Saturday, the United States said it had imposed sanctions on a Revolutionary Guards general in Khuzestan who commanded units Washington accused of responsibility for killing anti-government protesters in November.

The U.S. State Department cited “multiple” media reports and information submitted by Iranians through its “Rewards for Justice” tipline saying that Guards units killed as many as 148 protesters with machinegun fire and by setting fire to a marsh in which protesters took cover in the city of Mahshahr.

Iranian authorities disputed the U.S. account, saying security forces confronted “rioters” who they described as a security threat to petrochemical plants and to a key energy supply route that, if blocked, would have created a crisis.

Protests in November were initially sparked by hikes in gasoline prices but demonstrators quickly expanded their demands to cover calls for more political freedom and other issues.

The unrest prompted the bloodiest crackdown on demonstrators in the 40-year history of the Islamic Republic, which blamed foreign enemies for rising tensions.