Twitter confirmed on Tuesday, Oct. 13 that it had removed fake accounts posing as Black Donald Trump supporters, shortly after an investigation by Clemson University revealed that some fraudulent pages reached thousands of people before they disappeared.

“Our teams are working diligently to investigate this activity and will take action in line with the Twitter Rules if Tweets are found to be in violation. Presently, we’ve taken action on some of the Tweets and accounts…for violations of our policies on platform manipulation and spam,” a Twitter representative told The Hill.

The Washington Post reported Tuesday that more than a dozen fake accounts were used to spread misinformation on Twitter before the social media platform could take them down.

The fake accounts, many of which used identical language, appear to represent supposed Black Trump supporters, and recently garnered more than 265,000 retweets or mentions. Several of the accounts, which used what researchers refer to as “digital blackface” had tens of thousands of followers.

The accounts typically featured images of Black men, and claimed affiliation with stereotypically pro-Trump groups, like police organizations. Clemson researcher Darren Lindvill, who tracked the tweets, told the Washington Post he found traces of the Russian Cyrillic alphabet in the online records.

If Twitter is able to confirm that a tweet was produced through a “state-backed operation,” it will release the names of the countries involved. This month, Twitter suspended more than 100 accounts hacked by actors in Iran who were trying to interfere with politically and racially charged issues related to Black Lives Matter and George Floyd.

Fifteen accounts used the phrase: “YES IM BLACK AND IM VOTING FOR TRUMP!!!” One such account, @CopJrCliff, gained 24,000 followers in just six days of activity. Its most popular tweet was liked more than 75,000 times.

Researchers have speculated that the network creators have financial motives and wish to sell social media users Trump merchandise.

The profile picture of the @CopJrCliff account shows a Black police officer who supposedly lives in Philadelphia. However, the investigation showed that the image came from a 2017 article about a Portland officer named Jakhary Jackson. Jackson said on Tuesday he has never lived in Philadelphia and does not use social media.

“They are impersonating Black Trump supporters, Black authoritative figures such as veterans and police officers, and various prominent individuals in order to gain rapid traction and virality,” said Lee Foster of Mandiant Threat Intelligence.

Another account posed as a Black US Marine and married father of three who described himself as a “newly converted republican.” The account gained 18,000 followers before it was suspended.

One account with the phrase: “YES IM BLACK AND IM VOTING FOR TRUMP,” posed as a man named “Gary Ray,” and featured an image of a Black man. The picture is an image of a man named Robert Williams who called the use of his face on the account “an attempt to mislead people.”

His image is returned as a search result when the phrase “Black man” is entered.

Although the accounts have been suspended, computer science professor Filippo Menczer of IU Bloomington said the damage has already been done. “There is payoff just in getting the volume out there, and the fact that the original post is gone doesn’t really matter, he said to the Post.