Ghostbusters' Leslie Jones began the new cycle of criticism after leaving the service because of racist and sexist abuse / Getty Images

The move came after sustained criticism of the way that Twitter protects those who are attacked on the platform

Twitter has launched a crackdown on abuse as it attempts to deal with repeated criticism that it doesn’t do enough to protect its users.

The site has banned a range of its users – some forever – after Ghostbusters actor Leslie Jones left the service because of a torrent of racist and sexist abuse.

Jones initially shared some of the abusive tweets that have been sent to her since she starred in the new film. She then announced that the site wasn’t doing enough to keep her safe and that she would leave it.

"I leave Twitter tonight with tears and a very sad heart,” she posted. “All this cause I did a movie. You can hate the movie but the shit I got today...wrong."

That tweet prompted a response from CEO Jack Dorsey, asking Jones to talk to him. The site then launched a spree of bans, which included controversial users Milo Yiannopoulos, who was said to have led the abuse against Jones.

Twitter has long come under criticism for not doing enough to police abusive behavior on the often-freewheeling messaging service. Other celebrities have taken issue with abuse on the site, including writer and actress Lena Dunham, who said in September she had hired someone to tweet on her behalf because it was no longer a "safe space" for her.

Twitter said in a statement Tuesday that it had seen an "uptick" in the number of accounts violating its abuse and harassment policies over the past 48 hours, noting it had enforced its policies either by issuing warnings or permanently suspending users.

"We know many people believe we have not done enough to curb this type of behavior on Twitter. We agree," Twitter said in the statement. "We are continuing to invest heavily in improving our tools and enforcement systems to better allow us to identify and take faster action on abuse as it's happening and prevent repeat offenders."

Jones shared some of the racist tweets targeted toward her, many of which compared her to an ape. User YellowArmedImposter wrote, "Your Ghostbusters isn't the first to have an ape in it," which Jones shared with the comment: "I just don't understand."

Jones, who is also a regular cast member on Saturday Night Live, publicly pondered over several tweets what would prompt people to "spew hate."

"I used to wonder why some celebs don't have Twitter accts now I know," she wrote in one tweet. In a separate post, she added: "Twitter I understand you got free speech I get it. But there has to be some guidelines when you let spread like that."

Additional reporting by Reuters