A 21-year-old man has been arrested after a barrage of sexual abuse was posted on Twitter aimed at the woman who campaigned for a female figure to appear on British banknotes.
Caroline Criado-Perez received hostile posts, including threats to rape and kill her, nearly every minute in the 48 hours after she attended the Bank of England's unveiling of the new £10 note, with Jane Austen's image on, on Wednesday.
A Scotland Yard spokesman said: "A 21-year-old man has today been arrested in the Manchester area on suspicion of harassment offences.
"The arrest is in connection with an allegation of malicious communications received by officers in Camden on Thursday, July 25."
On Sunday, Ms Criado-Perez said she had been informed that an arrest had been made.
On her Twitter page she wrote: "Just heard from police that an arrest has been made. That's all I have at present."
She earlier called on the social networking site and police to take action over the abuse.
She told Sky News: "It was really really disturbing to find that something as small as asking for one woman on a banknote could result in such a barrage of threats of sexual violence.
"It's just not acceptable and more than that it's actually a crime and Twitter needs to take it seriously and the police need to take it seriously."
Her comments come as an online petition in support of her, calling on Twitter to introduce a button to allow speedy reporting of abuse, has attracted more than 25,000 signatures.
She has also received support from MPs and celebrities.
Ms Criado-Perez added: "This is something that happens specifically to women and it’s to make them shut up because there is a certain type of man who doesn't like women speaking and they don’t like women speaking back to them.
"I wasn't going to give them what they wanted so I decided to start being very very public about the abuse I was receiving even though it was really unpleasant and obviously it's invited more abuse to a certain extent, but it's also invited so much support which has been absolutely incredible."
A spokesperson for Twitter said: "The ability to report individual tweets for abuse is currently available on Twitter for iPhone and we plan to bring this functionality to other platforms, including Android and the web.
"We don't comment on individual accounts. However, we have rules which people agree to abide by when they sign up to Twitter.
"We will suspend accounts that, once reported to us, are found to be in breach of our rules.
"We encourage users to report an account for violation of the Twitter rules by using one of our report forms: https://support.twitter.com/forms ."
The Metropolitan Police is conducting inquiries into the matter after receiving an allegation of abuse.
Labour's shadow home secretary and shadow minister for women Yvette Cooper has written to the head of Twitter in the UK urging stronger action over the matter, saying she is "deeply concerned by the handling of serious and violent threats of abuse and rape".
The letter says: " ... Despite the scale and seriousness of these threats, the official response from Twitter continues to be extremely weak - simply directing Caroline away from Twitter towards the police, and, belatedly, directing users to abuse reporting forms on Twitter.
" ... I urge you to go further and ensure that Twitter carries out a full review of all its policies on abusive behaviour, threats and crimes, including more help for Twitter users who experience abuse, a clear complaints process and clear action from Twitter to tackle this kind of persecution."
Comedians Chris Addison and Dara O'Briain are among the celebrities to back Ms Criado-Perez with messages on Twitter.
Addison wrote: "In case you missed it, here's the link to petition to add a 'Report Abuse' button to Twitter … Least we can do, right?”
And O'Briain posted: "If the ladies leave Twitter because of all the dumb, rapey 14-year-old boys, then I'm outta here people. Like most grown-up men too, I'd say"
MPs including Stella Creasy and Diane Abbott also voiced their support via the microblogging site.
Ms Criado-Perez, a freelance journalist who co-founded The Women's Room , an online database of female experts, organised a campaign which included a petition signed by more than 35,500 people after the Bank of England decided to replace Elizabeth Fry with Winston Churchill on new £5 notes.
The move would have meant there were no women apart from the Queen on sterling banknotes.
Her campaign was a success, with an announcement by the Bank last week that Pride And Prejudice author Austen will replace Charles Darwin on the new £10 note when it is introduced 2017.