Multiple rockets hit near the US embassy in Iraq's capital early Sunday, an American military source said, the latest in a flurry of attacks against US assets in the country.
The assault sent warning sirens blaring across the diplomatic compound but it was unclear exactly what was hit and how many rockets made impact, the US source and a Western diplomat based nearby told French press agency AFP.
There were no immediate reports of casualties.
AFP correspondents on the ground heard multiple strong explosions followed by aircraft circling near the Green Zone, the high-security enclave where the US mission is located.
"No casualties. Investigation ongoing," a coalition spokesman said in a tweet Sunday without giving further details.
It was the 19th attack since October to target either the embassy or the roughly 5,200 US troops stationed alongside local forces across Iraq.
The attacks are never claimed but the US has pointed the finger at Iran-backed groups within the Hashed al-Shaabi, a military network officially incorporated into Iraq's state security forces.
Last month, the Iraqi parliament passed a resolution calling for an end to the presence of foreign troops linked to the US-led alliance fighting Islamic State.
Sunday's attack came just hours after one of the Hashed's Iran-backed factions, Harakat al-Nujaba, announced a "countdown" to ousting American forces from the country.
The resolution came after a US drone strike in Baghdad killed top Iranian Revolutionary Guard General Qassem Soleimani, later prompting Iranian missile attacks against Iraqi military bases housing US personnel.
In January, Iran threatened to attack US soil if it responded to the launch of of surface-to-surface missiles at Iraq’s Ain Assad air base housing US troops.
State TV described it as Tehran's revenge operation over the death of Soleimani, however no US troops or personnel were injured in what was largely a symbolic move designed to save face domestically, rather than prompt the US to retaliate.
Iran’s Revolutionary Guard has warned the US and its regional allies against retaliating over the missile attack in Iraq.
The country also called US President Donald Trump a "terrorist in a suit" after the US president threatened to hit 52 Iranian sites, as a conflict between the two countries escalated.
At the height of tensions last month, Iran shot down a passenger plane with an anti-aircraft missile killing all 176 people on board in what is believed to have been a mistake.
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