NEW YORK — Drops for stocks in the artificial-intelligence industry are dragging down markets worldwide on Thursday, while oil prices hit their highest levels since May because of worries about the war with Iran.

The S&P 500 sank 0.8 per cent following even sharper losses in Asia, whose markets are full of AI and other technology stocks. The Nasdaq composite was down 1.5 per cent, as of 10 a.m. Eastern time, but stocks outside of tech did better, and the Dow Jones Industrial Average was down a modest 0.1 per cent, or 60 points.

AI-related stocks have been shaky on worries that their boom may be…