U.S. strikes in Iraq and Syria overnight didn’t take long to provoke a reaction, despite claims that the strikes were a “deterrent.” US troops in Syria were under rocket attacks within a matter of hours.

Details are still emerging, though the U.S. says that there are no casualties so far. This is just the start of the problem though, with the targeted militia vowing “open war with the American occupation.”

U.S. troops reportedly came under rocket fire in northeastern Syria, and U.S. troops responded with artillery fire. Secretary of State Tony Blinken said that the U.S. is ready to act further.

Iraq’s umbrella militia Hashd al-Shaabi says four Iraqis were killed in the U.S. attacks, and promised to “wreak vengeance on the perpetrators of this heinous crime.” In the attack on Syria, the US killed at least one civilian child.

In addition to attacks in Syria, the group is threatening to target U.S. aircraft and fire missiles against U.S. bases in Iraq.

Many in Iraq are calling for revenge, while Iran issued a statement warning Biden that he is headed down the wrong path. Biden has touted this as a message to Iran.

This article was originally featured at Antiwar.com and is republished with permission.