Yemen’s Houthis say they attacked two Saudi oil tankers in the Red Sea after the United States launched its 12th consecutive night of strikes against Iran.

Iranian state media said two people were killed in Wednesday’s US strikes and that a tanker truck caught fire in an explosion on a mined road in the Strait of Hormuz.

Before the latest round of attacks, US President Donald Trump had threatened to destroy an Iranian bridge or power plant if Iran attacked a ship in the strait and to “take care” of the Houthis if they blocked the Red Sea.

If confirmed, the Houthi attack would be the first since the Iran-backed group announced a “maritime embargo” against Saudi Arabia.

The Houthis named the oil tankers Encelia and Layla, although neither their responsibility nor the attack on the Layla has been confirmed.

The group’s military spokesman, Yahya Saree, said they had attacked the ships with drones and missiles for allegedly violating their naval blockade.

Saree added that the Houthis promised to continue their naval operations and would continue to “apply the ‘siege for siege’ equation.”

The UK Maritime Trade Operation (UKMTO) reported that an “unknown projectile” hit a Saudi oil tanker about 130 kilometers from Al Shuqaiq in Saudi Arabia at 20:00 GMT. The attack caused a fire but there were no casualties, he said.

British maritime risk management group Vanguard also reported that the Saudi oil tanker Encelia had been hit, according to the Reuters news agency.

The US Central Command (Centcom) said at 21:30 GMT that it had launched strikes under Trump’s direction “to further degrade Iran’s ability to threaten civilian mariners and commercial vessels transiting regional waters.”

Kuwait, Jordan and Bahrain soon reported that they had responded to air threats, before the Iranian military said they had attacked US assets in all three countries, according to AFP.

Iranian state media reported that two people had been killed in US strikes in the south of the country, near its border with Iraq.

Meanwhile, the Iranian Revolutionary Guard (IRGC) said the Strait of Hormuz was “completely closed” after an explosion in the channel, Reuters reported.

The IRGC said it had prevented three oil tankers from passing through the strait.

One tanker caught fire and two others turned back after trying to pass through a mined route south of the Strait, according to Iranian state media.

It comes after Trump vowed on Wednesday to attack an Iranian bridge or power plant if his forces attacked ships in the Strait of Hormuz.

Iran’s Foreign Minister Abbas Araghchi later warned of a “tit for tat” response to attacks on Iran.

On Tuesday, Trump told reporters that he would “deal with the Houthis” if they blocked the Red Sea, as they had said.

The Houthis gave few details about the “maritime embargo” when they announced it on Monday, but a media official said they were closing the Bab al-Mandab Strait, the southern gateway to the Red Sea, to Saudi vessels.