Oil surges on Strait of Hormuz attacks as chip stocks tumble on Samsung earnings miss

Oil prices climbed sharply on Tuesday after reports that Iranian forces had attacked multiple commercial vessels moving through one of the world's most critical shipping lanes. U.S. crude jumped more than 3 percent to above $70 a barrel for the first time since July 1, while international Brent crude also rose 3 percent to exceed $74. The moves reflected immediate concern about disruption to global energy supplies from a waterway through which roughly a fifth of the world's traded oil passes each day.

The U.K.'s Maritime Trade Operations center reported two separate incidents in the Strait of Hormuz on Tuesday morning. One vessel had been struck by what officials described as an uncrewed aerial vehicle; a second ship was hit by an unidentified projectile and sustained structural damage. A third commercial vessel off the coast of Oman caught fire after being struck. A U.S. official confirmed to NBC News that Iran's Islamic Revolutionary Guard Corps had fired missiles at two of the ships and struck a third with at least one drone. The U.S. military responded by shooting down additional drones launched by Iranian forces. One of the damaged vessels, identified as the liquefied natural gas tanker Al Rekayyat, was reported by Reuters to be at risk of explosion due to a fire in its engine room, though NBC News could not independently verify that claim.

The attacks sent immediate ripples through financial markets. U.S. Treasury yields climbed alongside oil prices, with the 20- and 30-year yields breaking above 5 percent. The 10-year yield, which more directly affects consumer borrowing costs, reached its highest level since early June. Stock markets initially fell sharply on the news—the S&P 500 dropped nearly 1 percent at its low point—but recovered some ground by early afternoon, closing down only 0.3 percent.

The Nasdaq 100, however, suffered more substantial losses, falling as much as 2 percent. The decline was driven almost entirely by a collapse in semiconductor and technology stocks. Samsung, one of the world's largest chip and memory manufacturers, saw its shares plunge 7 percent overnight after reporting earnings that, while beating expectations, disappointed investors who had anticipated a larger margin of outperformance. The company's results came in 6 percent ahead of analyst estimates—a respectable beat that nonetheless fell short of what some market participants had priced in. Joe Mazzola, head of trading and derivatives strategy at Charles Schwab, described the move as a "wave of profit taking" that sent "shockwaves through the U.S. market" after a period in which investors had been actively buying volatile chip stocks.

Samsung's stumble reflected a broader fragility in technology valuations. Investors remain on edge about whether the enthusiasm driving artificial intelligence stocks can be sustained, and they have grown quick to sell on any sign of weakness. South Korea's Kospi Index briefly dipped into bear market territory—a decline of more than 20 percent from its recent peak—as other major chip manufacturers including SK Hynix also fell sharply. By early afternoon on the U.S. side, nine of the ten worst-performing stocks on the Nasdaq were either memory or chip companies, with Intel and SanDisk each down roughly 9 percent.

Adding to pressure on the semiconductor sector was a Reuters report that China's artificial intelligence startup DeepSeek is developing its own AI chip. If successful over time, such a development could reduce DeepSeek's dependence on chips from American suppliers, a prospect that unsettled investors already worried about the sustainability of the current chip-buying cycle. Meanwhile, SpaceX shares declined 5 percent despite making their debut as part of the Nasdaq 100 Index on Tuesday—a listing that typically triggers billions of dollars in automatic buying from index-tracking funds, though that support proved insufficient to offset broader market caution.