Iran’s Revolutionary Guard said it ​fired ballistic missiles at a base in Jordan used by the U.S. military and attacked 10 ships on Wednesday, after the U.S. said it had destroyed ‌five Iranian oil tankers, in a sharp escalation of the six-month-old war, Reuters reported.

Increased attacks by both the U.S. and Iran have shattered a month of relative calm, hitting military, shipping and energy assets, sending oil prices surging and drawing in regional allies in recent days.

The Americans said they destroyed five Iranian oil tankers on Tuesday. The U.S. military’s Central Command posted video of the strikes, which it called a response to Iran’s Islamic Revolutionary Guard Corps (IRGC) targeting ​a U.S. Navy warship twice with ballistic missiles over the previous two days. No Americans were harmed, the U.S. said.

“Iran continues to try to hit U.S. naval ships, and ​for every time they do that or try to do that, they’re going to lose tankers,” U.S. Secretary of State Marco Rubio told reporters ⁠during a visit to Colombia.

Iran then carried out a ballistic missile attack on a base used by U.S. forces near Al Azraq in Jordan, according to an IRGC statement on state ​media.

Although Iran said its missiles inflicted heavy damage, Jordan said its air defences intercepted 18 of the 20 Iranian missiles, with two falling in unpopulated areas, and that there were no casualties. A ​U.S. official said Iran’s strikes in Jordan were ineffective and all American troops were accounted for.

The IRGC said on Wednesday it also attacked 10 ships, including two U.S. vessels and eight oil tankers, attempting to cross a “prohibited and unsafe” area of the Strait of Hormuz, a vital energy conduit largely choked off by Iranian attacks.

Iran has targeted U.S. assets and allies in the region throughout the war, including in Jordan several times, killing at least ​two U.S. military personnel during one strike in July.

Iran has also threatened oil tankers in Kuwaiti and Bahraini ports, according to a statement carried by state media. A maritime security source ​reported a liquefied natural gas tanker was damaged in the Emirati port of Khor Fakkan, though it was unclear who was responsible.

Oil prices extended gains in early trade on Wednesday with Brent crude nearing $100 a barrel ‌on market ⁠concerns over the disruption of oil tanker traffic in the Strait of Hormuz. Recent attacks by Yemen’s Iran-aligned Houthis on top energy producer Saudi Arabia have added to supply concerns, read the report.

On Tuesday, Houthis launched an attack on several cities in Saudi Arabia, further undermining regional stability.

The Houthi attacks wounded 73 people and set oil installations ablaze in what appeared to be a major expansion of the conflict, which began on February 28 with joint U.S.-Israeli attacks on Iran.

The Houthis, who control most of Yemen’s populated areas, including the capital, have further pressured U.S. allies by ​periodically disrupting shipping on the other side of ​the Arabian Peninsula, at the entrance to ⁠the Red Sea.

They said they had launched a broad operation deep into Saudi territory, using drones and missiles to strike a Saudi air base in the southern city of Khamis Mushait as well as Saudi state oil company assets in the cities of Abha, Najran and Jazan.

Saudi authorities reported ​blazes at the sites and said women and children were among the wounded.

Saudi Arabia has led an Arab coalition battling against the Houthis ​in Yemen for more ⁠than a decade, after the Houthis drove the Yemeni government from the capital. That war had calmed in recent years, but a ceasefire there has broken down.

The wider war in the Gulf has turned into a test of wills between the U.S. and Iran, with each side hoping that economic pressure from competing blockades will force the other to yield.

Washington is trying to increase the flow of oil to ⁠world markets ​by guiding ships through the Strait of Hormuz, while cutting off Iran’s exports with a blockade,  Reuters reported.

Central Command said the ​tankers it destroyed on Tuesday were part of a shadow network that funds the IRGC and its regional proxies. Iran has long supported what it calls an “Axis of Resistance”, which includes the Palestinian Islamist group Hamas, Lebanon’s Hezbollah, Iraqi Shi’ite ​militias and the Houthis.

An average of 10 commodity ships transited the Strait of Hormuz per day over the past 10 days, the lowest since ​May, according to shipping data on Monday, after U.S. and Iranian ‌strikes on tankers, Reuters reported.

The 10-day moving average was 10 on Sunday, down from more than 15 on Friday and nearly 13 on Saturday, data from analytics firm Kpler found.

Only two ​vessels passed through the strait on Saturday while six went through on ​Sunday, mostly using the Iranian route.

U.S. forces struck three Iranian ⁠oil tankers on Saturday, U.S. Central Command said, including one off Kharg Island, Iran’s ​key oil export hub, following attacks by Iran’s Islamic Revolutionary Guard Corps on U.S. ​warships in the region.

In retaliation, the IRGC navy said on Saturday it targeted three oil tankers travelling unauthorized routes in the strait as well as three additional U.S. vessels in other areas.

The ​three Iranian tankers were Downy, Stark I and Kylo, also known as ​Noxen, maritime intelligence firm Marisks said in a note.

The Saturday attacks represented a “major escalation in the maritime conflict”, ‌Marisks said.

“Commercial ⁠tankers are now being deliberately used as instruments of reciprocal economic pressure, substantially weakening the previous distinction between military confrontation and commercial shipping,” it added.

“Risk is therefore assessed as extreme for Iranian/Iran-linked tonnage and materially elevated for U.S.-linked ​or U.S.-escorted shipping throughout ​the Strait of ⁠Hormuz and Gulf of Oman.”

There have been 27 projectile strike incidents since July 6, resulting in damage to vessels operating in ​and around the Strait of Hormuz, the United Kingdom Maritime ​Trade Operations (UKMTO) ⁠said in its weekly report.

On Sunday, one very large crude carrier and three bulk carriers laden with metals, grains or oilseeds entered the strait, Kpler data showed.

A ⁠tanker ​carrying refined products loaded from a Saudi port attempted ​to exit but was turned back, data from LSEG showed.

There has been no VLCC exiting the strait ​since Wednesday, according to Kpler data.

US and Iranian forces exchanged attacks involving vessels in waters around Iran on Saturday, in a sharp escalation that threatens to further disrupt energy supplies and deepen the conflict between the two countries.

US Central Command said it struck three Iranian oil carriers, including one near Kharg Island, Iran’s main oil export hub, after Iran’s Islamic Revolutionary Guard Corps (IRGC) fired ballistic missiles at two US Navy ships.

“If you shoot at two of our ships, we will impose an even higher economic cost,” US Central Command chief Admiral Brad Cooper said.

The IRGC warned that it would intensify attacks against US military vessels in the region. It later said it had targeted three tankers travelling on unauthorised routes through the Strait of Hormuz, as well as three US-linked vessels in other areas.

Iran’s Tasnim news agency reported that four US missiles struck a tanker near Kharg Island. It said there were no casualties and that the crew was being evacuated.

US Central Command said no American personnel were injured.

The latest exchange follows an escalation over the past week in a conflict that began after US and Israeli strikes on Iran in February. The fighting has disrupted global energy supplies and increased concerns over a wider regional confrontation.

Trump warns over Kharg Island

US President Donald Trump has continued to threaten military action against Iran, even as his administration expands economic sanctions.

On August 31, Trump posted an AI-generated video depicting Kharg Island being destroyed. Iranian authorities have warned of a strong response if the island is attacked.

Iran, the third-largest producer in OPEC, previously exported about 90% of its crude through Kharg Island. Oil flows have been disrupted since the US began a blockade of Iranian oil exports in mid-April.

Trump had previously threatened action against Kharg Island, saying in June that he wanted to take control of it before ruling out a US military operation there.

The US blockade followed Iran’s effective closure of the Strait of Hormuz, a key global energy route that previously carried about one-fifth of the world’s oil supply.