The navy of Iran's Islamic Revolution Guard Corps (IRGC) said Saturday it had targeted three oil tankers in the Strait of Hormuz and three U.S.-affiliated vessels elsewhere in retaliation for the U.S. attacks on Iranian tankers earlier in the day.

The three tankers that were struck in the strait were crossing the waterway through the "unauthorized" route, the navy said in a statement published on the IRGC's official news outlet Sepah News, adding the other three vessels were hit in other regions.

The navy also urged all vessels in the Gulf and near the Strait of Hormuz to refrain from being "deceived" by the U.S. Army and any suspicious movement to transit the waterway through "unauthorized" routes, otherwise they will be targeted.

Earlier in the day, Iran's state-run IRIB news agency reported that three Iranian oil tankers were attacked by the U.S. Army off Iran's southern coasts.

Following the incident, Ebrahim Zolfaghari, spokesman of Iran's main military command, Khatam al-Anbiya Central Headquarters, warned the United States against continuing its attacks on Iranian vessels as well as the naval blockade against the country.

"If the malice and insecurity against and harassment of Iranian ships, as well as the anti-Iran naval blockade continue, the strikes by the armed forces of the Islamic Republic of Iran against U.S. military vessels in the region will become more severe than before, and there is a possibility of their expansion," Zolfaghari said in a statement carried by Iranian media.

Following the U.S.-Israeli strikes on Iran on Feb. 28, Tehran restricted passage through the Strait of Hormuz, barring vessels linked to the United States or Israel, while U.S. forces imposed a naval blockade targeting vessels traveling to or from Iranian ports and coastal areas.