Two oil tankers were attacked within minutes of each other while passing through the Strait of Hormuz on Monday, reflecting continued risk for ships exporting oil from the Persian Gulf. A crude oil tanker owned by Saudi Arabia's national oil company was struck by "unknown projectiles" about 16 nautical miles off the coast of Oman, according to Marisks, a maritime risk firm. A second ship, a Liberian-flagged supertanker operated by the South Korean company Sinokor, was also struck off Oman's coast.

No casualties or environmental impact were reported. On Tuesday, U.S. forces struck Islamic Revolutionary Guards Corps targets in retaliation. Oil prices jumped about 4 percent, pushing the global benchmark above $90 a barrel.

Marisks advised ships to delay nonessential transits. Founder Dimitris Maniatis said Iran targets vessels based on affiliations with the United States and allies. Only five ships passed through the strait Monday, the lowest since early May, down from more than 130 daily before the war. There have been more than 72 attacks on ships since March, with at least 19 sailors killed, according to the International Maritime Organization.