A 21-year-old man has been arrested in Manchester on suspicion of harassment offences after feminist campaigner Caroline Criado-Perez was targeted on Twitter.
Scotland Yard confirmed the arrest is in connection with an allegation of malicious communications received by officers in London on Thursday.
Ms Criado-Perez, who successfully campaigned for the Bath author Jane Austen's picture to be put on a new bank note, has received a deluge of threats from various sources on the microblogging site.
Twitter has faced calls to take faster and stronger action against online abuse in the wake of the incident.
A feminist campaigner who successfully pushed for a campaign for the Bath author Jane Austen to be put on a new bank note, has become a target of abuse on Twitter.
Caroline Criado-Perez has faced a deluge of hostile tweets over the course of more than a day, including threats to rape and kill her.
Ms Criado Perez said: "It's sadly not unusual to get this kind of abuse but I've never seen it get as intense or aggressive as this.
"It's infuriating that that the price you pay for standing up for women is 24 hours of rape threats
"We are showing that by standing together we can make a real difference. We made the Bank of England change its mind, we can do the same with Twitter", she added.