The U.S. military launched new strikes against Iranian targets around the Strait of Hormuz on Tuesday, U.S. Central Command said in a social media post, after a pair of oil tankers came under attack in the critical shipping route.

The strikes come after President Donald Trump had reportedly been considering a CENTCOM plan for limited attacks aimed at preventing Iran from rebuilding radar and missile capabilities that could be used to target ships in the strait.

CENTCOM said U.S. forces began striking Islamic Revolutionary Guard Corps targets in Iran at noon ET, following what it described as recent attempted attacks by the IRGC against commercial shipping in the Strait of Hormuz and U.S. service members deployed to the region.

The scope of Tuesday’s operation was not immediately clear. CENTCOM did not disclose how many targets were struck, their locations or what U.S. military assets were involved.

The operation marks a new escalation after the U.S. and Iran exchanged fire over the weekend for the first time in roughly a month. 

On Sunday, the U.S. military struck rocket launchers on Iran’s Larak Island after CENTCOM said Iranian forces were preparing to fire rockets carrying sea mines into the strait.

Tehran responded by launching missiles at U.S. sites in Jordan that were intercepted. The United Arab Emirates also said it intercepted an Iranian drone over its territorial waters.

Trump threatened further retaliation Monday, telling Fox News, “We’re going to hit them hard. There will be a response.”

The U.S. Embassy in Qatar issued a security alert Tuesday warning of the potential for “unforeseen escalation” and urging Americans in the region to exercise heightened vigilance amid possible flight cancellations, airspace closures and other travel disruptions.

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