A fresh air strike hit pro-Iran fighters in Iraq early Saturday, as fears grew of a proxy war erupting between Washington and Tehran a day after an American drone strike killed a top Iranian general.
The killing of Quds Force commander Major General Qasem Soleimani in Baghdad on Friday was the most dramatic escalation yet in spiralling tensions between Iran and the United States, which pledged to send more troops to the region -- even as President Donald Trump insisted he did not want war.
Iran's ambassador to the United Nations, Majid Takht Ravanchi, told CNN that the killing was an "act of war on the part of the United States".
A new strike on Saturday targeted a convoy belonging to the Hashed al-Shaabi, an Iraqi paramilitary network dominated by Shiite factions with close ties to Iran.
The Hashed did not say who it held responsible but Iraqi state television reported it was a US air strike.
A police source told AFP the strike left "dead and wounded," without providing a specific toll. There was no immediate comment from the US.
It came hours ahead of a planned a mourning march for Soleimani, who was killed alongside Hashed number two Abu Mahdi al-Muhandis in the precision drone strike.
As head of Iran's Revolutionary Guard Corps' foreign operations arm, Soleimani was a powerful figure domestically and oversaw wide-ranging Iranian involvement in regional power struggles -- and anti-US forces.
Trump said the 62-year-old, who had been blacklisted by the US, had been plotting imminent attacks on American diplomats.
His assassination has rattled the region, with Iraqis fearing a proxy war between Washington and Tehran.
A total of five Revolutionary Guards and five Hashed fighters were killed in Friday's strike near Baghdad international airport.
Their bodies will be laid tom rest in an elaborate mourning procession on Saturday, beginning with a state funeral in the capital and ending in the Shiite holy city of Najaf to its south.
The bodies of the Guards will then be flown to Iran, which has declared three days of mourning for Soleimani.
Tehran has already named his deputy, Esmail Qaani, to replace him.
Supreme leader Ayatollah Ali Khamenei promised "severe revenge," while in Tehran tens of thousands of protesters torched US flags and chanted "death to America."
Trump hailed the operation, saying he decided to "terminate" Soleimani after discovering he was preparing an "imminent" attack on US diplomats and troops.
He insisted Friday Washington did not seek a wider conflict, saying: "We took action last night to stop a war. We did not take action to start a war."
But hours later the Pentagon said between 3,000 to 3,500 troops would be dispatched to Iraq's southern neighbour Kuwait.
Secretary of State Mike Pompeo praised Washington's partners in the region, but said their European allies "haven't been as helpful as I wish that they could be".
"The Brits, the French, the Germans all need to understand that what we did, what the Americans did, saved lives in Europe as well," he said.
Some 14,000 troops were already deployed as reinforcements to the Middle East last year, reflecting steadily growing tensions with Iran.
There are approximately 5,200 US troops deployed across Iraq to help local forces ensure a lasting defeat of Islamic State group fighters.
Soleimani had long been considered a lethal foe by US lawmakers and presidents, with Trump saying he should have been killed "many years ago".
Following Friday's strike, the embassy urged US citizens to leave Iraq immediately and American staff were being evacuated from oil fields in the south.
Analysts said the strike, which sent world oil prices soaring, would be a game-changer.
"Trump changed the rules -- he wanted (Soleimani) eliminated," said Ramzy Mardini, a researcher at the US Institute of Peace.
Phillip Smyth, a US-based specialist on Shiite armed groups, described the killing as "the most major decapitation strike that the US has ever pulled off."
He expected "bigger" ramifications than either the 2011 operation that killed Al-Qaeda chief Osama bin Laden or the 2019 raid that killed IS leader Abu Bakr al-Baghdadi.
Iraq's caretaker prime minister Adel Abdel Mahdi warned the strike would "spark a devastating war in Iraq" as President Barham Saleh pleaded "voices of reason" to prevail.