US President Donald Trump has courted controversy with his use of social media platform Twitter, so it makes sense he would have many followers.
But a suspicious jump in followers over the past few days has caught the attention of many Twitter users.
Since the weekend, Mr Trump's number of followers on his @realDonaldTrump account has gone up by at least three million to 31 million.
And if one looks through the list of followers, one sees pages of accounts with no profile pictures, no followers and no posts. They also appear to have been made in May 2017.
Website Twitter Audit says nearly half Mr Trump's Twitter followers are fake.
"Each audit takes a sample of up to 5000 Twitter followers for a user and calculates a score for each follower," the website says.
"Of course, this scoring method is not perfect but it is a good way to tell if someone with lots of followers is likely to have increased their follower count by inorganic, fraudulent, or dishonest means."