"Two missiles were fired from a fighter jet" at the same base in Anbar province that was struck on Tuesday, the official said.

He reported that there were some casualties, but did not give further details.

Tuesday's strike was the deadliest in Iraq since the start of the Middle East war on February 28, killing 15 fighters including a commander.

The Hashed, also known as the Popular Mobilisation Force (PMF), blamed that strike on the United States.

The former paramilitary coalition is now part of Iraq's regular armed forces, but also includes brigades belonging to Iran-backed groups.

The attack prompted the government late on Tuesday to grant the PMF a "right to respond" to any attack against them.

Throughout Tuesday evening and into Wednesday morning, the sounds of military aircraft flying over the capital Baghdad were particularly loud, AFP journalists reported.

Since the war began, pro-Iran armed groups have claimed responsibility for attacks on US interests in Iraq and across the region, while strikes have also targeted these groups, including on state-linked positions.

The Pentagon has acknowledged that combat helicopters carried out strikes against pro-Iran armed groups in Iraq during the current conflict.

Baghdad has condemned attacks targeting foreign soldiers and diplomatic missions, as well as strikes against PMF positions.