An unidentified account holder impersonating an Australian feminist bought offensive promoted tweets from the social media company, which ran them despite internal policies that ban such messages. The account holder also tweeted similar anti-transgender messages using Twitter’s traditional news feed.

After receiving multiple reports about the abusive tweets, Twitter suspended the account on Tuesday and deleted the ads.

This isn’t the first time that the victim of the impersonation, Caitlin Roper, had been targeted with fake accounts. She’s also been attacked by men’s rights groups, including A Voice For Men, for her political and philosophical views. However, it is not clear whether any of them were behind Tuesday’s incident.

Here are some of the complaints posted on Twitter about the offensive messages:

https://twitter.com/youngvulgarian/status/601036114061828096

Hi friends, someone has created a Twitter account impersonating me and tweeting hateful comments. Account suspended, thanks for your help x

— Caitlin Roper (@caitlin_roper) May 20, 2015

In December, Twitter announced improvements to the way users report abuse on the service after intense criticism that it did too little to delete abusive posts. Users can now flag inappropriate without jumping through as many hoops. Twitter also made it easier for users to report abuse of others and introduced new filters to help them block threatening content before it reaches their feeds.

Though the reporting system seems to have worked in this case, it’s still unclear how the promoted tweet slipped through Twitter’s advertising program.

When reached for comment, Twitter (TWTR) told The Guardian: “As soon as we were made aware we removed the ad and suspended the account.”

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