Oil Price Surges, Stocks Tumble on Middle East Fears

Investors ran for the hills on news of the attacks and a warning from Tehran that its regional foe faced a "bitter and painful" fate. 

Main oil contracts, which had rallied earlier in the week on rising tensions, spiked more than 12 percent, hitting levels not seen since January, amid fears about supplies of the commodity.

They later eased back slightly after Iran said its key refineries and fuel depots were unaffected.

The rush from risk assets to safe havens saw equity markets tumble and bonds rally with gold, which popped above $3,400 an ounce. 

"The Middle East powder keg just blew the lid off global markets," said Stephen Innes at SPI Asset Management.

"Brent crude futures are racing toward the mid-$70s range, but if the Strait of Hormuz, which accounts for 20 percent of global oil flows, finds itself in the blast radius, you can add another $15 to the bid,” he said.