Shares of technology companies fell as a flight from the sector resumed. Apple, Microsoft and other mega cap tech companies lost ground.

Shares of Tesla plunged by more than 9% after the electric car maker's much hyped "Battery Day" turned out to be an anticlimax. Chief Executive Elon Musk unveiled advances on battery technology that could be meaningful for electric-vehicle development in the long term but hardly justified the rampant speculation on the car maker's stock in advance of the event.

Talks between Tesla rival, electric-truck maker Nikola, and several potential partners, including BP, to build hydrogen-refueling stations stalled following allegations the company had misled investors, The Wall Street Journal reported.

Chinese state media denounced a White House-approved plan to turn TikTok into a U.S.-based company, casting more doubt over plans for Oracle and Walmart to buy a stake in the Chinese-owned short-video app that needs nods from both Beijing and Washington to avoid a ban in the U.S.

Write to Rob Curran at rob.curran@dowjones.com