The strikes - the 10th consecutive night of attacks - come after US President Donald Trump vowed to punish Iran for the deaths of US soldiers. In response, Iran said it struck two oil tankers in the waterway, as well as US military assets in Bahrain, Kuwait and Jordan, state news agency IRNA reported.
President Masoud Pezeshkian said Iran was now fighting a "full-scale war" with the US. Trump earlier said Iran had been hit "very hard" the previous night "in honour" of three US soldiers killed recently - two in Jordan and one in Iraq.
US Central Command (Centcom) said its latest strikes had hit Iranian "military command centres, maritime capabilities, missile and drone launch sites, and air defence systems".