The US says it has carried out air strikes against Iran-backed militias near the Iraq-Syria border in response to drone attacks on its forces in Iraq.
A Pentagon spokesman said the strikes targeted “operational and weapons storage facilities” at three locations, reports BBC.
President Biden had been clear he would act to protect US personnel, he added.
A powerful Iraqi militia alliance, the Popular Mobilisation Forces (PMF), said four members of one faction were killed and threatened to retaliate.
About 2,500 US troops are in Iraq as part of a global coalition supporting local security forces in their fight against the jihadist group Islamic State (IS).
There have been at least five drone attacks against facilities they use since April, US officials say. Rockets are also frequently fired at them.
Iraq’s military said the strikes represented a clear breach of Iraqi sovereignty.
Military spokesman Gen Yehia Rasool tweeted: “We condemn the US air attack that targeted a site last night on the Iraqi-Syrian border, which represents a blatant and unacceptable violation of Iraqi sovereignty and Iraqi national security.”
He reiterated Iraq’s “refusal to be an arena for settling scores” and appealed for calm.
Iran also condemned the strikes. Foreign Ministry spokesman Saeed Khatibzadeh told reporters in Tehran that the US should “refrain from taking emotional steps, creating crises and tensions, and multiplying problems for people in the region”.
Syrian state media reported that a child was killed in a strike near Syria’s border with Iraq, and accused the US of seeking to undermine efforts to improve stability in the area.
Pentagon spokesman John Kirby said the “defensive precision air strikes” that took place early on Monday were intended to “disrupt and deter” further drone attacks on US personnel in Iraq.
The targeted facilities were at two locations in Syria and one inside Iraq, and were used by several Iran-backed groups, including Kataib Hezbollah and Kataib Sayyid al-Shuhada, the Pentagon said.
US media reported that the strikes – the second round targeting Iran-backed militias ordered by President Biden since he took office in January – were carried out by US Air Force F-15s and F-16s using satellite-guided munitions.
“The United States took necessary, appropriate, and deliberate action designed to limit the risk of escalation – but also to send a clear and unambiguous deterrent message,” Mr Kirby said.
The US has designated Kataib Hezbollah as a foreign terrorist organisation since 2009 and has accused it of carrying out many attacks against US forces in Iraq in recent years. Its leader, Abu Mahdi al-Muhandis, was killed alongside top Iranian general Qasem Soleimani in a US drone strike in Baghdad last year.
Kataib Hezbollah and Kataib Sayyid al-Shuhada were both targeted in US air strikes in eastern Syria in late February in response to a rocket attack on a US-led coalition airbase in Irbil that killed one Filipino civilian contractor.
Iraqi militia alliance the PMF said Monday’s strikes “resulted in the martyrdom of a group of heroic fighters”.
“We will remain the shield defending our beloved nation, and we are fully ready… to respond and take revenge,” it warned.
Syria’s state-run Sana news agency said a child was killed and three civilians were injured when warplanes bombed several houses near the Syrian border town of Albu Kamal at about 01:00 on Monday (22:00 GMT on Sunday).
Sana also cited a PMF source as saying that four militia fighters were killed and three others wounded in strikes on their positions near the al-Qaim border crossing, inside Iraqi territory.
The Syrian Observatory for Human Rights, a UK-based monitoring group, reported that at least seven militia fighters were killed in the strikes.
The strikes come as Iran and world powers attempt to revive a 2015 nuclear deal.
The agreement has been close to collapse since 2018, when then-US President Donald Trump abandoned it and reinstated sanctions that have crippled the Iranian economy. Iran retaliated by gradually breaching agreed limits on its nuclear activities.
