(Updates with index/price moves, macroeconomic data, and geopolitical news from the first paragraph.)
US equity indexes slumped as a sell-off in chipmakers hit technology, and Iran warned its allies would close the Red Sea crude oil chokepoint if President Donald Trump orders an attack on Tehran's civilian infrastructure.
The Nasdaq declined 1.5% to 25,881.95, the S&P 500 fell 0.5% to 7,533.77, and the Dow Jones Industrial Average declined 0.2% to 52,552.97 on Thursday. Communication services and technology led decliners, while consumer staples, health care, and real estate topped the gainers.
Shares of Taiwan Semiconductor Manufacturing (TSM) slid 2.3% after the firm earmarked an additional $100 billion to increase its chipmaking capacity in the US, raising its total planned investment to $265 billion, Bloomberg reported Thursday, citing a US official. Taiwan Semiconductor also reported Q2 results on Thursday, with year-over-year earnings and net revenue rising and Q3 sales guidance beating consensus.
Among stocks with market capitalization exceeding $200 billion each, 13 out of the bottom 20 names were from the technology sector, according to data compiled by Finviz. Almost half of the decliners were semiconductor firms, the data showed. The worst performer was SanDisk (SNDK), down about 12.6%.
In geopolitical news, the US military launched a sixth consecutive night of strikes on Iran, with the country's media reporting explosions on Qeshm Island, Bandar Abbas, and Chabahar, according to Al Jazeera, a Middle Eastern broadcaster.
The Iranian military has warned "all infrastructure in the region will be crushed under steel blows" if the US carries out its threat to attack Iran's civilian sites, the Al Jazeera report said. Iran has asked Yemen's Houthi movement to stand ready to close the Red Sea oil route if the US strikes Iranian power infrastructure, Reuters reported, citing three sources.
Total volumes of petroleum transiting Bab el-Mandeb amounted to 7.4 million barrels per day in June, or about 7% of global oil output, up from 4.2 million bpd a year ago, MarineLink reported, citing Kpler data.
The front-month US West Texas Intermediate fell 0.7% to $79.08 a barrel, hovering around its highest in about a month amid a rally that began after the US renewed strikes on Iran a week ago. North Sea Brent futures retreated 0.7% to $84.34 a barrel, close to its month-high.
Iraqi crude loadings more than doubled to average roughly 1.2 million barrels per day in the first half of July, Reuters reported, citing Kpler data and a source with direct knowledge of the flows, as exports accelerated following months of restricted shipments.
Most US Treasury yields rose, with the 10-year up 1.2 basis points to 4.56% and the two-year climbing 1.7 basis points to 4.15%.
In precious metal markets, gold futures retreated 1.8% to $3,980.5, and silver futures dropped 2.8% to $55.84.
In economic news, US retail sales rose by 0.2% in June, as expected in a Bloomberg-compiled poll and following the previous month's revised 1.0% increase.
US initial jobless claims fell to a level of 208,000 in the week ended July 11 from an upwardly revised 216,000 level in the previous week, compared with expectations for a level of 217,000 in a survey of analysts compiled by Bloomberg.