The Iraqi government condemned U.S. airstrikes launched inside Syria and Iraq Tuesday, saying that the strikes were an attacks on its sovereignty.

The country's Foreign Ministry said that it would summon the U.S. ambassador to discuss the strikes launched Sunday against sites controlled by the Kataeb Hezbollah Militia.

"We stress that Iraq is an independent country, and its internal security takes priority, and serious attention, and will not be allowed to become a battlefield, or a route for launching attacks," it said in a statement about what it planned to tell the U.S. ambassador.

The statement said that the future presence of U.S.-led coalition forces fighting ISIS in Iraq would be discussed.

The U.S. launched the attacks following a rocket strike Friday attributed to Kataeb Hezbollah militia that killed a U.S. military contractor working with Iraqi and U.S. forces.

The KH militia, which is calling for retaliation, says at least 25 of its fighters were killed in the strikes and dozens more were injured.

KH and more than two dozen other Iran-backed militias have a complicated position within Iraq.

The paramilitary group has fought against ISIS and is formally part of Iraq's security forces – though U.S. officials have raised concerns about whether the Iraqi government actually has control over it and other Iran-backed groups.

A U.S. State Department official said the latest military action was "designed to protect American forces and American citizens in Iraq, but it is also aimed at deterring Iran."

"[This militia] has been for months now, firing mortars and rockets at U.S. forces at locations throughout Iraq," NPR's Tom Bowman reported.

The U.S. government blamed the militia for a recent attack on an Iraqi base near the city of Kirkuk that killed a U.S. contractor.

The attack involved more than 30 rockets fired at the base used by U.S. and Iraqi forces and injured four U.S. service members in addition to two Iraqi troops, according to the Defense Department.

The U.S. military says it launched "precision defensive strikes" against three of the militia's facilities in Iraq and two in Syria. Jonathan Hoffman, an assistant to the Secretary of Defense, said in a statement that the locations "included weapon storage facilities and command and control locations that KH uses to plan and execute attacks on [Operation Inherent Resolve] coalition forces." Some of these led to large secondary explosions, as Bowman reported.

Hoffman stressed that KH has a strong link to Iran's elite Quds Force, and said it has received weapons and other support from Iran that it turned on coalition forces.

"The U.S. and its coalition partners fully respect Iraqi sovereignty, and support a strong and independent Iraq," Hoffman stated. "The U.S., however, will not be deterred from exercising its right of self-defense."

"Our battle with America and its mercenaries is now open to all possibilities," KH said in a statement after the strikes, according to The Associated Press. "We have no alternative today other than confrontation and there is nothing that will prevent us from responding to this crime."

Previous KH strikes had not caused serious injuries. But they were enough to worry U.S. officials. In May, as Bowman reported, "Secretary Mike Pompeo abruptly canceled a trip to Germany and flew to Baghdad because I'm told intelligence showed the possibility of a large attack on U.S. forces, presumably by these militias." That threat did not materialize at the time.

Iraqi Prime Minister Adel Abdul-Mahdi office's said in a statement that he received a call from U.S. Defense Secretary Mark Esper shortly before the airstrikes, and asked for them to be called off. Abdul-Mahdi decried the strikes as a unilateral act by the U.S.-led coalition that are considered a violation of Iraq's sovereignty.

A State Department official told reporters that the U.S. is not worried about the potential consequences of the strikes. They added that it's the Iraqi government's "responsibility and duty to protect us, and they have not taken the appropriate steps to do so." The State Department reports that there have been 11 attacks on Iraqi bases that host coalition forces in the last two months. "This obviously is a campaign," the official said.

The Iranian embassy also published a statement in Iraqi local media, calling the strikes against militias a violation of Iraqi sovereignty.

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