One person was killed and eight wounded in an overnight explosion at an Iraqi military base housing a coalition of pro-Iranian armed groups, officials said on April 20.
The full details remain unclear hours after the blast hit the Kalsu military base in Babylon province south of Baghdad, where regular Army, police and members of Iraq's Popular Mobilisation Forces, or Hashed al-Shaabi, are stationed.
It comes days after Iran launched an unprecedented assault on Israel which reportedly responded with a drone strike on the Islamic republic, amid tensions fuelled by the Gaza war.
The Iraqi security forces' media unit said "an explosion and a fire" hit the Kalsu base in the early hours of Saturday, leaving one person dead and eight wounded.
Air defence command reported "no drones or combat aircraft in the airspace of Babylon province before or during the explosion", it added in a statement.
There was no immediate claim of responsibility.
Shortly after the explosion, the U.S. military said its forces were not behind a reported strike in Iraq.
"The United States has not conducted air strikes in Iraq today," U.S. Central Command (CENTCOM) posted on social media platform X, adding that reports that American forces had carried out a strike were "not true".
The Israeli Army said it "does not comment on information published in foreign media".
In a statement, Hashed al-Shaabi said an "explosion" had inflicted "material losses" and casualties, without giving a number.
The group said investigators had been sent to the site.
On Saturday morning, however, the Hashed issued another statement that referred to a meeting between its chief of staff and investigation committees "on the site that has been attacked".
'Odious crime'
An Interior Ministry official had initially reported an "aerial bombing" on the site.
"The explosion hit equipment, weapons and vehicles," said the source.
An Iraqi military official, who spoke on condition of anonymity due to the sensitivity of the subject, said the overnight explosion had occurred in "warehouses storing equipment".
Responding to questions from AFP, neither the interior ministry official nor the military official could say who may have been behind the alleged bombing.
The Hashed al-Shaabi is an integral part of the official Iraqi security apparatus under the authority of the prime minister.
It brings together several pro-Iran armed factions, some of which have also carried out dozens of attacks in Iraq and Syria against U.S. forces deployed as part of an international anti-jihadist coalition.
"We will retaliate against whoever is behind this aggression," Hashed commander Abu Alaa al-Walai wrote on X, formerly Twitter. "Those involved in this odious crime will pay the price."
On Friday, strikes blamed on Israel targeted a military base near the city of Isfahan in central Iran.
The explosion came in response to Tehran's unprecedented attack on Israel last weekend, in retaliation for a deadly strike on Iran's embassy in Damascus.
Iraq's foreign ministry expressed "strong concern" on Friday over the blast in Iran, warning of the "risks of military escalation which threatens security and stability in the region".
"This escalation must not be allowed to divert attention from what's happening in the Gaza Strip," it said.
Iraqi Prime Minister Mohamed Shia al-Sudani is in Washington, where he met US President Joe Biden this week.
