Twitter has unveiled a "report tweet" button for users to instantly flag abusive messages after a campaign for increased safety measures on the site.
The campaign to "Take Back Twitter" was launched last month after several high-profile women were targeted in violent and sexually explicit messages.
Feminist campaigner Caroline Criado-Perez received rape and death threats after successfully campaigning to put author Jane Austen on the £10 bank note.
Stella Creasy, the Labour MP for Walthamstow in east London, was also targeted for defending Criado-Perez, whilea number of female journalists were sent bomb threats.
Criado-Perez said the new function was a "fantastic first step".
"It's great that Twitter has listened," she said. "There are still issues: users have to agree for the report to be potentially shared with the harasser, and there are some boxes that could be auto-populated that aren't. But overall, this is a fantastic first step."
Kim Graham, who started the Change.org petition for Twitter to beef-up protection measures, said the in-Tweet button was a welcome move forward.
"I'm thrilled that Twitter has started making progress on this.
"Online bullying and harassment has been too common for too long, and this is a very welcome first step toward online safety for women."
She added: "There are always improvements that can be made, but this proves that if we speak up together we can really have an impact."
Following the abuse, Twitter UK's general manager Tony Wang apologised to the women.
Three people were also arrested in connection with the threats and Scotland Yard's e-crime unit reported it was investigating eight people on the site for abuse.
More than 120,000 people signed a petition urging Twitter to implement tighter processes to protect its users.
The site has since clarified its rules on abusive behaviour and brought in extra staff to deal with trolls.
The in-Tweet button is available across iPhone, Android and Twitter.com, and allows users to flag individual tweets rather than go through its Help Centre.