Two explosives-laden drones targeting an Iraqi military base housing US troops in western Anbar province have been destroyed, officials said.
It is the second such attempted attack coinciding with the anniversary of the 2020 US air strike that killed a top Iranian general near Baghdad airport.
On Monday, two armed drones were shot down as they headed toward a facility housing US advisers at the airport.
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According to the official, the fixed-wing drones rigged with explosives were engaged and destroyed by defensive capabilities at the Ain al-Asad airbase.
An Iraqi military statement confirmed the attempted attack, saying the drones were shot down outside the parameters of the base.
The facility houses troops with the US-led international coalition fighting the so-called Islamic State group (IS) in Iraq.
In Monday's attack, the drones were shot down by the C-RAM defence system that protects American installations in Iraq, and there were no reports of damage or injuries from the incident.
No group claimed responsibility for the attack, although one of the wings of the drones had the words "Soleimani's revenge" painted on it, according to the coalition and Iraqi officials.
"These are attacks against Iraqi installations and an attack against the Iraqi people and the military that protects them," a coalition official said.
"We maintain a minimal footprint on Iraqi bases. The coalition no longer has its own bases in Iraq."
The 2020 US drone strike at Baghdad's airport killed Gen Qassim Soleimani, who was the head of Iran's elite Quds Force, and Abu Mahdi al-Muhandis, deputy commander of Iran-backed militias in Iraq known as the Popular Mobilisation Forces.
Pro-Iran Shia factions in Iraq have vowed revenge over the killing and have conditioned the end of attacks against the US presence in Iraq on the full exit of American troops from the country.
The US-led coalition formally ended its combat mission supporting Iraqi forces in the ongoing fight against IS last month.
Some 2,500 troops will remain as the coalition shifts to an advisory mission to continue supporting Iraqi forces.
"While we have ended our combat mission, we maintain the inherent right of self-defence," the coalition official said.