ERBIL -- An explosives-packed drone slammed into Erbil airport in Iraq's Kurdish region on Wednesday (April 14) in the first reported use of such a weapon against a base used by international coalition troops in the country, officials said.
There were no casualties, although the strike did cause damage to a building in the military part of the airport.
It comes after around 20 bomb and rocket attacks blamed on Iran-aligned Iraqi militias against facilities used by international coalition troops or diplomats in the past few months.
The attacks mostly have been claimed by a new crop of shadowy militias aligned with Iran that has emerged in Iraq over the last year, at least 15 in total.
These "smokescreen" militias are generally understood to be fronts for the three most prominent Iran-backed militias operating in Iraq: Kataib Hizbullah, Harakat al-Nujaba and Asaib Ahl al-Haq.
"A drone packed with TNT targeted a coalition base at Erbil airport," the Kurdish region's interior ministry said in a statement.
There was no immediate claim of responsibility for the attack, which caused an explosion heard across Erbil.
But a shadowy pro-Iran front group calling itself Saraya Awliyaa al-Dam (Guardians of Blood Brigades), which claimed responsibility for a previous attack on the same airport in February, hailed the strike on the messaging app Telegram.
In the February attack, more than a dozen rockets targeted the military complex inside the airport, killing an Iraqi civilian and a foreign contractor working with international coalition troops.
Washington said it was "outraged" by the latest violence.
"The Iraqi people have suffered for far too long from this kind of violence and violation of their sovereignty," State Department spokesman Ned Price said.
Drones linked to Iran
A senior US defence official told AFP that while Wednesday's strike marked the first use of a drone to target US troops inside Iraq, Iran's allies in the country had already shown they had the technology.
Washington has said a January drone attack on the Saudi capital Riyadh was carried out from southern Iraq on behalf of Yemen's Iran-backed Houthis (Ansarallah).
"The Iranian-backed militias have drones now with a 15-foot (four and a half metre) wingspan," the defence official said.
"It's an Iranian-made CAS-04 which we've already seen weaponised by the Houthis against Saudi."
The official said the technology was constantly being improved.
"They now have the capacity for a rocket-assisted launch. The range is 1,200-1,500km (750 to 930 miles) if they add fuel tanks to it," he said.
"They can even be loaded onto a ship from (the Iraqi port of) Basra and brought even closer to target. These can be pre-programmed with a GPS destination."
'Dangerous escalation'
Iraq's President Barham Saleh condemned the latest attack and urged all Iraqis to unite against the "terrorists" behind it.
"Once again, infrastructure has been targeted in Erbil as it has been before in Baghdad and elsewhere," he said. "These terrorist crimes ... require us to unite behind the security forces to enforce the law on the terrorists."
Former foreign minister Hoshyar Zebari explicitly blamed a pro-Iran "militia" for the attack.
"It seems the same militia who targeted the airport two months ago are at it again," Zebari said on Twitter. "This is a clear & dangerous escalation."
As pro-Iran groups ratchet up their rhetoric, there have been almost daily attacks on international coalition supply convoys across the country's south.
Earlier Wednesday, two roadside bombs exploded as convoys passed through the southern provinces of Dhi Qar and Diwaniyah, security sources said.
Last week, the administration of US President Joe Biden resumed a "strategic dialogue" with the government of Prime Minister Mustafa Kadhemi which includes discussion of withdrawing all remaining combat forces from Iraq.