Iraq's Popular Mobilisation Forces (PMF) said that an investigation was under way after a bombing overnight on Friday at an Iraqi military base housing pro-Iranian armed groups.
The attack killed one member of the PMF and wounded at least eight people, including an Iraqi army personnel, the office of Iraqi Prime Minister Mohammed Shia Al Sudani said on Saturday.
Iraqi security sources said it was most likely carried out by Israel, adding that fighter jets were used, and not drones, as was previously reported.
The Islamic Resistance in Iraq, a group of pro-Iranian armed groups claimed on Saturday morning that it had attacked Eilat in Israel, in response to the strike.
Palestinian group Hamas strongly condemned the attack, calling it a blatant breach of Iraq's sovereignty and security and a manifestation of the "Zionist barbarism that expands its aggression on the region."
Images on social media showed a large fire at the Kalsu base
The base reportedly houses PMF units, Iraqi army and federal police forces.
The PMF claimed the US was responsible for the attack.
US Central Command posted a statement on X disputing the reports, saying that “the United States has not conducted air strikes in Iraq today”.
Iraqi militias have halted attacks on US forces since February 4 due to a truce between Washington and Tehran, but are claiming attacks against Israel on a regular basis.
In January, the US struck targets in Iraq and Syria following attacks on American troops in the region.
The reported air strike comes as Iraqi Prime Minister Mohammed Shia Al Sudani is concluding a visit to Washington during which he discussed plans for the withdrawal of US and allied troops from the country.
The explosion on the Iraqi military base comes amid tensions over the war between Israel and Iran-backed Palestinian militants Hamas.
On Friday, strikes blamed on Israel fell on a military base near the city of Isfahan in central Iran.
Israeli officials made no public comment on Friday's attack and Iranian officials have played down its significance.
