Television classicist Mary Beard has received a bomb threat on Twitter just hours after the UK Twitter boss personally apologised to her and other women who had been sent threats on the site.
Ms Beard, a professor of classics at University of Cambridge, said she had contacted police after receiving a message on Saturday evening claiming a bomb had been left outside her home.
Prof Beard, 58, told BBC Radio Five Live: "There's something very strangely and awkwardly insidious about it.
"It is scary and it has got to stop. I didn't actually intellectually feel that I was in danger but I thought I was being harassed, and and I thought I was being harassed in a particularly unpleasant way."
She wrote on her Twitter page: "Just got 1 of these messages. A bomb has been placed outside your home. It will go off at exactly 10.47pm and destroy everything. Told police."
Later that evening, she added: "OK all, it's 11.00pm and we are still here. So unless the trolling bombers timekeeping is rotten.... all is well. But how stupidly nasty."
Ms Beard then took to Twitter the following morning and said she had planned to be off Twitter for a day of Twitter silence in response to the so-called "trolls", but she had received more abuse.
"Planned to be off twitter, but I've had more threats this morning (rape and worse). It IS still going on. Tried to report to Twitter, failed", she said in a tweet.
The 24 hour #Twittersilence has been spearheaded by Caitlin Moran and is being observed by many Twitter users today.
Independent columnist Grace Dent, Guardian columnist Hadley Freeman, and Europe editor of Time magazine Catherine Mayer, as well as a number of other women, have alleged they had been the subject of bomb threats on the site, while two received threats of rape.
Tony Wang, Twitter UK general manager, personally apologised to the women affected in a series of tweets on Saturday, describing abuse as "simply not acceptable".
His messages came after the website clarified its rules on threatening behaviour amid growing criticism after a series of threatening tweets were widely publicised.
Mr Wang wrote: "I personally apologise to the women who have experienced abuse on Twitter and for what they have gone through.
"The abuse they've received is simply not acceptable. It's not acceptable in the real world, and it's not acceptable on Twitter.
"There is more we can and will be doing to protect our users against abuse. That is our commitment."
Twitter also responded to an online petition calling for Twitter to introduce a "report abuse" button to tweets which attracted more than 124,000 signatures, by adding an "in-tweet" report button. Users can now report abusive behaviour directly from a tweet, the social networking giant said.
The move comes as Scotland Yard confirmed its e-crime unit was investigating allegations by eight people of abuse on the microblogging site.
In separate incidents, Labour MP Stella Creasy and campaigner Caroline Criado-Perez, who successfully fought for a woman's face to appear on £10 banknotes, were threatened on Twitter with rape. Two arrests have already been made in relation to those threats.
The anonymous Twitter accounts from which the bomb threats originated were suspended, although screen grabs were widely circulated online.
Scotland Yard said an investigation into eight allegations had been launched.
The force said: "Detectives from the Specialist Organised & Economic Crime Command have taken responsibility for the investigations into a number of allegations recently made to the MPS relating to allegations of malicious communication made on the social networking site Twitter.
"The Police Central e-Crime Unit (PCeU), who hold the police national cyber crime remit, is now investigating allegations made by eight people that they have been subject to harassment, malicious communication or bomb threats."
It said the decision was taken to centralise the individual investigations, including three from outside London.