U.S. troops in northeast Syria came less than rocket fire Monday night after Iran-backed militias vowed revenge for U.S. airstrikes earlier that day in Iraq and Syria, a indication that battling may be evolving into sustained confrontation.

A spokesman for the U.S.-led coalition, Col. Wayne Marotto, explained that a number of rockets experienced been fired at U.S. troops and that American forces responded by firing artillery at the rocket launching positions. There ended up no U.S. accidents, he additional.

The rocket attack, which a professional-militia information agency explained experienced occurred close to Syria’s al-Omar oil discipline, came as the Biden administration warned Monday that it stood prepared to protect U.S. troops.

Secretary of Condition Antony Blinken explained that President Biden is “fully geared up to act and act correctly and intentionally to safeguard U.S. interests,” if Iran-backed militia continued to attack American forces in the location.

The U.S. airstrikes, which Iran-backed militia groups explained killed 4 of their associates, spotlight the problem struggling with the Biden administration as it attempts to discourage assaults without provoking an escalation.