The US military has conducted multiple air strikes in Syria against Iran-aligned groups, following a deadly drone attack that killed an American contractor and injured another, along with five US troops. The Pentagon said the attack against US personnel took place at a coalition base near Hasakah in northeast Syria on Thursday. The US intelligence community assessed that the drone was Iranian in origin, further straining tensions between Washington and Tehran. US Defense Secretary Lloyd Austin said the retaliatory strikes targeted facilities used by groups affiliated with Iran's Islamic Revolutionary Guards Corps. The number of casualties is highly unusual, despite attempted drone attacks against US personnel in Syria being somewhat common.