The release of a less capital-intensive artificial intelligence model from China’s DeepSeek sent a chill through the U.S. stock market Monday, initiating a massive selloff underscoring the fragile backdrop behind the record market.

The tech-heavy Nasdaq slipped 2.8% Monday morning as a perceived threat from Chinese artificial intelligence startup DeepSeek prompted a global sell-off of tech stocks.

Stock index futures tumbled Monday as concerns about the AI rally ramped up in the face of buzz about China AI startup DeepSeek, sparking a risk-off move. Nasdaq futures (US100:IND) -3.5% tumbled. AI names like Nvidia (NVDA) and Super Micro Computer (SMCI) were down more than 10%.