President Donald Trump confirmed that US forces struck Iran on Monday night, at a target he described as a “minor attack” on an anti-aircraft facility.

“They built an anti-aircraft facility… As soon as it was completed, we hit it last night very nicely,” he said in a Fox News interview. Iran’s state-run IRNA news agency also reported several explosions on Qeshm Island, near the entrance to the strait. The US deliberately kept the attacks quiet to reduce the risk of escalation, according to The Wall Street Journal, which first reported the strikes, and one US official described the strikes as “defensive.” According to that report, in one exchange the Revolutionary Guard fired a surface-to-air missile at a US warplane, which fired back in self-defense, and another strike came after the US intercepted a missile fired from Qeshm at a commercial vessel. Iran said it downed a US MQ-9 Reaper drone and two Lucas drones near the Strait of Hormuz on Tuesday.