It’s not clear how many tweets and comments were deleted by Blackout, which was shut down for three weeks after a string of deadly shootings at Umpqua Community College.
Twitter confirmed that more than 1,000 tweets and 15,000 comments were scrubbed in the aftermath of the mass shooting at the school on October 1.
But the number of deleted tweets and conversations is smaller than the number deleted from Blackout’s platform, according to Twitter.
Blackout is a free platform that lets users tweet content anonymously and has been the subject of several lawsuits in recent years, including one filed by the U.S. Justice Department.
The company said that in some cases, the deleted tweets were not related to a crime, such as a tweet about a crime that never happened.
Blackouts were the result of the social media platform’s “inadequate controls” and a lack of a “meaningful system of reporting,” Twitter said.
Twitter’s Blackout policy did not specifically mention the mass shootings at the college or a tweet by a Umpqi student, who later killed himself.
Twitter said that it is now taking steps to improve its reporting systems to ensure that people are not unfairly targeted by Twitter’s automated systems.
Twitter is also working to provide users with “a clearer way to report abuse, including the ability to flag abusive accounts,” the company said.
The FBI is investigating two mass shootings that took place at U.C.L.A. and in Oregon.
The U.K.’s prime minister, Theresa May, and British Prime Minister Boris Johnson have both expressed concern about how Twitter handles and actions can impact people’s safety.
Twitter has said that the company is taking steps “to address any issues” that may exist.