Stock futures tumbled in overnight trading after the U.S. and Israel attacked Iran over the weekend, causing oil prices to surge and adding an unstable Middle East to a list of growing worries for equity investors.

Futures on the Dow Jones Industrial Average dropped 571 points, or 1.2%. S&P 500 futures lost 1% and Nasdaq 100 futures declined a little more than 1%. Gold futures jumped 2% as investors piled into the global safe haven.

The joint U.S.-Israeli strikes killed Supreme Leader Ayatollah Ali Khamenei, marking a watershed moment for the Islamic Republic and one of its most consequential episodes since 1979. President Donald Trump told CNBC’s Joe Kernen that U.S. military operations in Iran are “ahead of schedule,” but investors are worried about a prolonged conflict despite those comments.

The large-scale assault was launched overnight Saturday after Iran refused American demands to curb its nuclear program. Iranian officials have vowed a forceful retaliation, raising fears the conflict could spread across the region.

“The tail risk of a sustained conflict is higher than in 2024 or 2025, though we don’t see this war escalating to a point where it drastically changes the US outlook,” said Barclays’ Ajay Rajadhyaksha in a note. But early this week “is too early to buy any dip, especially with investors used to a pattern of quick de-escalation.”