Trump vows retaliation against Iran after U.S. deaths: 'They will pay'

President Donald Trump vowed that the U.S. would retaliate harshly after three American service members were killed during recent fighting with Iran.

"Every time Iran kills an American Soldier they will pay for that killing many times over!" Trump wrote on Truth Social, adding that he has delivered that "directive" to "every Leader in the Military."

The angry post came after the U.S. military attacked a range of Iran's military sites and assets overnight as it worked to clear the Strait of Hormuz for oil tankers and other commercial vessels that have been blocked during the war.

U.S. Central Command on Sunday night targeted "Iranian military command centers, air defense and coastal surveillance sites, maritime capabilities, missile and drone launch sites, and communications networks," it said in a post on X.

The three-hour barrage of strikes "further diminish Iran's ability to attack commercial vessels and civilian mariners transiting the Strait of Hormuz," Centcom said.

But traffic through the strait, the economically vital waterway that 20% of the world's oil passed through before the war began in late February, remains far below its prewar averages. Just 30 "verified transits" in the strait were identified between Friday and Sunday, tracking firm Kpler said Monday morning.

The strain on global oil supplies caused by the tumult in the strait threatened to get even worse Monday, when Iran-backed Houthi militants in Yemen declared a maritime embargo against Saudi Arabia.

Oil prices on Monday morning nevertheless ticked lower, after Iran's Foreign Ministry spokesman said messages are still being exchanged through intermediaries despite the escalating conflict. But prices edged back up following Trump's post.

Brent crude futures, the international benchmark, were last seen trading 32 cents higher at $88.42 per barrel. U.S. West Texas Intermediate crude futures were up 1 cent to $82.50 per barrel.

Both Washington and Tehran have repeatedly accused each other of violating a temporary ceasefire deal reached in June. Trump, frustrated by continuing hostilities centered around the Hormuz Strait, this month declared the ceasefire "over," prompting the U.S. to restart its retaliatory blockade of Iranian ports in the Gulf.

The U.S. death toll from the Iran war has now risen to 17. Iranian authorities said Sunday that at least 50 people were killed and more than 500 wounded in the renewed U.S. strikes this month.

"The memorandum said little about how disputed incidents would be investigated or how a breach in one area would affect obligations elsewhere," Michael Feller, chief strategist at Geopolitical Strategy, said of the June deal. The memorandum's ambiguity meant the incident quickly became a dispute over whether the agreement still existed, he noted.

U.S. strikes have widened in recent days to target civilian infrastructure, including the Bonji desalination plant that cut off water supplies to about 10,000 people.

Tehran has also retaliated across the Gulf with fresh attacks on targets in neighboring countries, including Bahrain, Saudi Arabia and Jordan. The Kuwaiti army said Monday that its air defense systems were intercepting "hostile" drone attacks from Iran.

The U.S. Embassy in Bahrain's capital, Manama, said Monday that it has information suggesting Iran may seek to target unspecified locations in the city. Sirens sounded across Bahrain as authorities urged residents to take shelter.

Iran's Revolutionary Guard said Monday that two oil tankers "exploded" attempting to travel through the "unsafe and dangerous route south of the Strait of Hormuz." The Iranian authority has warned vessels against using the U.S. and Oman-backed southern corridor, insisting that only Iranian-designated routes are permitted.

Despite the reported slowdown of traffic through the strait, U.S. officials insisted flows were still holding up. Energy Secretary Chris Wright said Sunday that about two-thirds of pre-conflict traffic — roughly 14 million barrels a day — is moving through the choke point. Around 20 million barrels of crude oil and refined products passed through the waterway before the war.

In an interview with ABC on Sunday, Wright said public reports indicating most shipping traffic has stopped in recent days are not true, estimating it was at about two-third of normal flow.