An explosion has hit an Iraqi military base housing pro-Iranian paramilitaries, according to security sources.

The explosion on Friday night was at the Calso base, where former pro-Iranian paramilitary group Hashed al-Shaabi – now integrated into the regular army – is stationed, an interior ministry source and a military official told Agence France-Presse.

The ministry official said the attack killed one person and wounded eight others, while the military source said three Iraqi military personnel were wounded, according to AFP.

The Reuters news agency said two officials blamed the explosion on an airstrike but could not say who was responsible.

In a statement, Hashed al-Shaabi said the attack had inflicted “material losses” and casualties, without specifying the number of wounded. The organisation said an “explosion” had hit its premises.

“The explosion hit equipment, weapons and vehicles,” said the ministry source.

The security sources would not identify who was responsible for the attack or say whether it had been a drone strike. There was no immediate claim of responsibility for the attack.

On social media, the US military said its forces were not behind the reported strike. “The United States has not conducted air strikes in Iraq today,” US Central Command (Centcom) posted on Twitter/X, adding that reports that American forces had carried out a strike were “not true”.

Hashed al-Shaabi, an alliance of mainly Shia armed groups formed to fight Islamic State, is now a part of Iraq’s security forces. It is also variously known as the Popular Mobilization Forces, People’s Mobilization Committee or the Popular Mobilization Units.

The attack on the pro-Iranian paramilitaries comes amid regional tensions over the war between Israel and Tehran-backed Palestinian-militants Hamas.

On Friday, strikes blamed on Israel targeted a military base near Isfahan in Iran, in apparent retaliation for a largely failed Iranian attempt to carpet-bomb Israel with drones and missiles.

With Agence France-Presse and Reuters