Iran has launched fresh missile attacks against United States targets in the Middle East, escalating the six-month-old conflict after American forces destroyed five Iranian oil tankers.

Iran’s Islamic Revolutionary Guard Corps (IRGC) said it targeted the US Al-Azraq air base in Jordan on Wednesday, with state media reporting damage to facilities used for aircraft maintenance, deployment and shelter.

Jordan’s military, however, said it intercepted 18 Iranian missiles fired towards the kingdom.

The latest escalation followed Iran’s warning that oil tankers operating off the coasts of US allies Kuwait and Bahrain would also be targeted in retaliation for the destruction of its vessels.

The IRGC said it had attacked 20 US vessels attempting to navigate the Strait of Hormuz, a strategically important waterway through which a significant share of global oil and liquefied natural gas normally passes.

Iran has maintained control over the strait since the conflict began in February, with maritime traffic through the route severely disrupted. Tehran has required vessels seeking passage to obtain permission and pay transit fees.

The confrontation has also triggered a fresh surge in global oil prices as markets reacted to the threat of further disruption to Middle Eastern energy supplies.

Brent crude rose to $99.46 per barrel in Asian morning trading, while West Texas Intermediate, the US benchmark, climbed to $94.45 per barrel.

The United States said its recent attacks on Iranian tankers were carried out after Iran targeted an American warship, marking the second reported attack on a US naval vessel in less than a week.

US Secretary of State Marco Rubio said Tuesday that Washington would continue responding to Iranian attacks on American naval forces by targeting Iranian tankers.

“Iran continues to try to hit US naval ships, and for every time they do that or try to do that, they’re going to lose tankers,” Rubio told reporters during a visit to Colombia.

The US military said its forces instructed the crews of the five Iranian oil tankers to abandon the vessels before they were destroyed.

The attacks prompted threats from Iranian military officials, who had previously warned that US bases across the region would be targeted if American forces struck Iranian oil tankers.

Iranian media also reported that a US missile hit a tanker near Kharg Island on Tuesday, although no casualties were reported.

The escalating confrontation has also involved unmanned military equipment. Iran’s Revolutionary Guards said Tuesday that they had seized what they described as one of the United States’ most modern unmanned submarine drones in the Strait of Hormuz.

The US military disputed the claim, saying the drone had malfunctioned and was an older model that did not contain sensitive information.

Iranian state television further reported that the Revolutionary Guards had fired ballistic missiles at two US destroyers, although the US military had not immediately confirmed the claim.

The continuing hostilities have deepened concerns over the security of the Strait of Hormuz, with prolonged disruption threatening global energy supplies and putting further pressure on crude prices.