World shares and U.S. futures have retreated after oil prices jumped more than 2%. European markets opened lower Thursday and benchmarks in Seoul and Hong Kong fell more than 3%. Tokyo's Nikkei 225 fell 2.7%. The price of Brent crude oil was hovering near $112 per barrel after Iran's state television reported that seven oil tankers caught fire after being targeted or striking naval mines in the Strait of Hormuz. On Wednesday, the S&P 500 added 0.6% and the Dow Jones Industrial Average added 0.7%. The Nasdaq composite climbed 1.1%. A much better profit report from SpaceX than analysts expected boosted AI-related stocks, along with Elon Musk's other publicly traded company, Tesla.