Instagram is investigating a bug that led some of its top users to lose millions of followers.
American singer Ariana Grande, who has the third most followed Instagram account, told fans she has lost three million followers, with her numbers falling from 145 million to 142 million.
Model Kylie Jenner saw her follower numbers wiped by 2 million, as did singer Selena Gomez.
The drop comes as social networking sites try to purge fake accounts and so-called “bots” that send out spam messages.
Instagram said it was investigating the issue.
While social media sites have periodically taken to removing large numbers of accounts that they believe are not real people or are simply spam, Instagram indicated this was not the result of a wider planned cut in users.