The United States launched a new attack against Iran on Sunday night, continuing days of attacks between the two countries. Iranian state media reported that the strikes killed one person in southwestern Iran, while four were injured.

Within hours of the new US attacks, Iran’s Islamic Revolutionary Guard Corps (IRGC) said it had attacked US military bases in Kuwait, Jordan and Bahrain.

The escalation of attacks, which casts doubt on the future of the interim US-Iran deal signed in June, comes amid conflicting claims about whether the Strait of Hormuz is open.

Iran says it has closed the key waterway until further notice, while the United States insists it is open.

Oil prices rose Monday morning in Asia. Brent crude rose 4% to $79.07 (£59.11) a barrel, while US-traded oil gained 4.2% to $74.53.

Energy prices on global wholesale markets have swung wildly in recent months as traders reacted to conflict developments.

Shortly after the United States and Israel attacked Iran on February 28, Tehran effectively closed the Strait of Hormuz, through which about 20% of the world’s oil and liquefied natural gas (LNG) typically passes.

Despite the latest gains, prices are well below the $120 per barrel Brent hit in late April.

On Sunday night, Centcom announced another round of attacks against Iran, which it said began at 17:00 ET (22:00 BST).

Dozens of Iranian military targets were later said to have been attacked, including air defense systems, coastal radar sites, and missile and drone capabilities.

U.S. forces were “prepared to ensure that freedom of navigation remains available for commercial shipping despite Iran’s continued unjustified aggression, harassment, threats and arbitrary statements,” Centcom said.

Minutes before Centcom’s initial announcement, Iranian state television reported explosions in Sirik, Qeshm, Bandar Abbas and Jask.

“Following the attack by the American enemy on Monday morning… one person was martyred and four others were injured,” IRNA reported, citing deputy governor for security and law enforcement in Khuzestan province, Valiollah Hayati.

The new wave of US strikes came after US forces attacked 140 Iranian military targets, Centcom said late Saturday.

Iran’s Islamic Revolutionary Guard Corps (IRGC) responded to those attacks with wide-ranging strikes against US bases and allies across the region, marking an escalation in the scale of hostilities.

Iran’s targets include Qatar, a mediator in the ceasefire talks that had not been attacked since April, and the United Arab Emirates, which had not been attacked since May. The BBC has contacted US Central Command (Centcom) for comment on an attack in Jordan.

The new fire has jeopardized a provisional ceasefire agreement signed last month, which aimed to reopen the strait and ultimately put a permanent end to the conflict.

Earlier this week, US President Donald Trump declared that the Iranian attacks meant the ceasefire was over, while Iranian Foreign Minister Abbas Araghchi accused the US of violating the agreement.

However, Trump said talks would continue and that mediators were trying to revive the process.

On Sunday, US Central Command insisted that the Strait was open and warned that the US military was in a position to ensure it flowed freely.

Additional reporting by Goncheh Habibiazad.