The United States has carried out air strikes in Iraq after a base hosting coalition forces suffered a deadly attack.
This week, a rocket attack on Camp Taji killed one British Army medic and two American service members, injuring several others.
Now, American air strikes have responded by targeting Iran-backed militia facilities suspected of carrying out the Camp Taji attack.
The US Department of Defense said in a statement: "The United States conducted defensive precision strikes against Kata'ib Hizbollah (KH) facilities across Iraq.
"These strikes targeted five weapon storage facilities to significantly degrade their ability to conduct future attacks against Operation Inherent Resolve (OIR) coalition forces.
"These strikes were defensive, proportional, and in direct response to the threat posed by Iranian-backed Shia militia groups (SMG) who continue to attack bases hosting OIR coalition forces."
Wednesday's attack on Camp Taji saw "more than 15 small rockets" target the base, according to the US military, and took the life of British soldier Lance Corporal Brodie Gillon.
Kata'ib Hezbollah are associated with the Islamic Revolutionary Guard, thought to be responsible for thousands of civilian and western military deaths.
The Camp Taji attack took place on the same date as the birthday of Iranian general, Qassem Soleimani - the former commander of the Islamic Revolutionary Guards elite Quds Force unit, killed by US forces in January.
UK Defence Secretary Ben Wallace said: "The coalition stands shoulder to shoulder in Iraq.
"Our forces work together to help the country resist the malign activity of terrorists.
"When we and others are attacked we reserve the right to defend ourselves.
"We support the right of the United States to defend themselves, as they have done.
"We reiterate that those who seek to harm our armed forces can expect to receive a strong response."
In response to the American response, UK Foreign Secretary Dominic Raab said: "The response to the cowardly attack on Coalition forces in Iraq has been swift, decisive and proportionate.
"We will continue working with our partners to ensure those responsible for these deplorable acts will be held to account."
These sentiments were echoed by US Defense Secretary Mark Esper on Twitter.
"The United States will not tolerate Iran-backed attacks against our people, our interests, and our Allies," he said.
"All options are on the table as we work with our partners to bring the perpetrators to justice, and maintain deterrence."
In the military statement confirming the attack, the US warned militias in affiliation with Iran failing to cease attacks on coalition forces, or "face consequences at a time and place" of its choosing.
Cover image: US Army paratroopers at Camp Taji in January (Picture: US Department of Defense).