U.S. stocks slumped on Tuesday under the weight of another jump for the price of oil. It was a return to form for financial markets after Wall Street’s worries about Israel’s fighting with Iran had seemed to calm a bit on Monday.

Stocks sank under increasing pressure from crude oil prices, which climbed in their latest see-saw move. A barrel of benchmark U.S. crude jumped 4.5% to $73.42. Brent crude, the international standard, added 4.5% to $76.54 per barrel.

Oil prices dropped and stocks gained in early trading on Monday, indicating optimism among investors about the limits of economic fallout from the ongoing conflict.