The Iraqi authorities said on Saturday that they are investigating an explosion that struck a base belonging to the Popular Mobilization Forces, a coalition of militias allied with Iran, resulting in one death and eight injuries.

Militia officials initially described the explosion that occurred at the Kalsu military base north of Babylon - a former American base that was handed over to the Iraqi army in 2011 - as an airstrike, blaming American forces. The U.S. Central Command denied in a statement that any airstrikes had been carried out in Iraq.

The Popular Mobilization Forces described the explosion in a statement on Saturday afternoon as an "attack" but did not blame any specific party.

The Iraqi security media stated that the country's air defense command did not detect any drones or fighter jets in the skies over Babylon before or during the explosion, adding that one member of the Popular Mobilization Forces was killed and eight were injured, including a soldier in the Iraqi army.

The Popular Mobilization Forces are a coalition of Iranian-backed Shia armed groups that have been classified as an "independent military formation" within the Iraqi armed forces.

In recent months, some of the member groups of the Popular Mobilization Forces have launched attacks on U.S. forces stationed in Iraq and Syria, which they said were a response to Washington's support for Israel in its war against Hamas in Gaza. Those attacks ceased at the end of January after three American soldiers were killed in a raid on a base in Jordan, near the Syrian border, prompting the U.S. to carry out retaliatory strikes in Iraq.

The explosion at the Popular Mobilization Forces base came a day after a suspected Israeli raid in Iran, where a broad array of Iranian-backed militias calling themselves the Islamic Resistance in Iraq stated on Saturday that they launched a drone attack on the Israeli city of Eilat on the Red Sea in response to what they described as "Israel's violation of Iraqi sovereignty in its treacherous targeting of Iraq's Popular Mobilization camps."

There were no reports in Israel about an attack on Eilat, and there was no immediate comment from the Israeli military.