The Iranian Navy targeted three oil tankers traveling through the Strait of Hormuz and three US-affiliated ships in retaliation for the three oil tankers hit earlier in the day by US forces, the Islamic Revolutionary Guard Corps (IRGC) claimed on Saturday.
US Central Command (CENTCOM) has not confirmed the strikes.
The IRGC warned against ships transiting the strait through routes unauthorized by Iran.
"Do not be deceived by the 'terrorist' US military and refrain from any suspicious movement aimed at passing through unauthorized waterways," the IRGC Navy said in a statement carried on Iranian state TV. "Otherwise, you will be targeted."
The IRGC later announced that it attacked a US aircraft carrier and destroyer with ballistic missiles, according to Reuters, though the US has not confirmed this.
Retaliation for US strike on three Iranian tankers
This comes after the US struck three Iranian oil tankers earlier in the day, according to CENTCOM.
One such tanker was reportedly struck off the coast of Kharg Island, near Iran's key oil export hub, with Tasnim, the semi-official Iranian news agency, reporting that four US missiles hit a tanker in the region.
CENTCOM said that the strikes were carried out after the IRGC launched ballistic missiles at two US Navy ships.
“Let the message to the IRGC be clear: If you shoot at two of our ships, we will impose an even higher economic cost - taking out three of yours," said Admiral Brad Cooper, head of CENTCOM.
Iran threatened intensified strikes against US military vessels in the region after the US strikes.
"If the evil, insecurity and harassment of Iranian ships and the naval blockade of Iran continue, the strikes of the Islamic Republic of Iran's armed forces against US military vessels in the region will be more severe than before, and there is a possibility of their expansion," Iran's military command said in a post on state media.