A U.S. military base near a major oil field in eastern Syria came under attack Monday, one day after the Biden administration launched airstrikes in Syria and Iraq targeting an Iranian-backed militia. The U.S. responded by firing artillery at nearby rocket launching positions. On Monday, President Biden defended his decision to order airstrikes.

President Joe Biden: “I directed last night’s airstrikes targeting sites used by the Iranian-backed militia groups responsible for recent attacks on the U.S. personnel in Iraq. And I have the authority under Article II, and even those up in the Hill who are reluctant to acknowledge that have acknowledged that’s the case.”

This comes as criticism of the U.S. airstrikes grows. Iraq’s prime minister condemned the U.S. attack as a “blatant and unacceptable violation of Iraqi sovereignty and Iraqi national security.”