TikTok greeted users opening the app Saturday night with the message, "Sorry, TikTok isn't available right now.".
The app also appeared to be removed from Apple and Google's app stores in the U.S., making it unavailable to download.
The notice TikTok users are getting when they try to use the app on Saturday.
Other Bytedance apps including CapCut, Lemon8 and Gauth displayed similar messages and also became unavailable to many U.S. users Saturday evening.
The shut down of TikTok follows several tense days of uncertainty for the app leading up to Sunday, when a ban on TikTok is supposed to go into effect in the United States.
Since the law was made, it became deeply unpopular with users and many Americans, and many TikTok users began fleeing to Chinese social media apps.
Many TikTok users have flooded a Chinese app called RedNote in protest of the government, but it poses an even greater security threat than TikTok, according to experts who spoke with NBC News. »