Seven oil tankers caught fire or were damaged in the Strait of Hormuz overnight into Thursday after being targeted or striking naval mines, Iranian state media reported.
Iran's Islamic Revolutionary Guard Corps Navy, meanwhile, claimed that four of the vessels were involved in illegal oil transfers in the northern Persian Gulf. They were simultaneously hit and caught fire after being tracked by its forces Wednesday.
The IRGC added that three more vessels collided with mines west of the Strait of Hormuz.
The markedly high number of vessels affected in Hormuz, pointed to tensions winding upward over concerns about a return to all-out war.
With days before Israel’s close elections in which Prime Minister Benjamin Netanyahu could lose power and ahead of next month’s U.S. midterm elections in which war-linked high prices have sparked voter anger, there are concerns that U.S.-Israeli attacks on Iran could resume.
Iranian state television reported the claims about the latest attacks on ships, citing the Revolutionary Guard Corps navy, which again threatened to strike U.S. military bases in the region if the U.S. keeps helping to guide commercial ships through the strait.
The report did not mention casualties. A British military monitor, the United Kingdom Maritime Trade Operations, did not report the attacks, but monitors in recent days have noted reluctance by some shippers to report incidents.
Iran still asserts control over the waterway, a central point of leverage in any talks with the U.S. over the war.
Iran’s top diplomat, Abbas Araghchi, on Wednesday said a wary Tehran remains open to diplomacy but is ready to defend itself.
Iran has warned that it has learned important military lessons from the war that began with U.S. and Israeli attacks on Feb. 28.
In recent days, Tehran has indicated it could expand targets to include infrastructure such as undersea cables and data centers.
The United States for its part is sending more military assets to the region, including a third aircraft carrier and thousands of troops, to join the largest force of American warships and aircraft in the Middle East in decades.
Mediators, meanwhile, have been trying to bring Washington and Tehran back to formal talks.
Iran is still promoting its latest proposal that would end the war and fully open the strait within a week if the U.S. meets several conditions. Those conditions, which include ending the U.S. blockade of Iranian ports, echo ones in the deal that fell apart within days of Washington and Tehran signing it in June.
U.S. President Donald Trump rejected that latest seven-day proposal, but both sides have acknowledged that indirect discussions have continued. Since that rejection, attacks on ships transiting the Strait of Hormuz have increased.
A return to all-out war would again endanger civilians throughout the region and complicate global deliveries of oil, natural gas and related products like fertilizer from the region and likely bring another spike in prices.