A feminist campaigner subjected to rape and death threats on Twitter has deleted her account on the site, a day after raising concerns about the police investigation into the abuse.

Caroline Criado-Perez, from north London, was subjected to a string of violent and obscene messages after she was involved in a campaign to have a woman's picture printed on a new banknote.

On Thursday, she claimed police had lost evidence linked to the case, which was denied by Scotland Yard, and criticised officers for a lack of sensitivity.

She said: "It's just appalling. I got an email saying 'why don't you go through what you've had' from three users with certain handles. It just shows such insensitivity to someone who's been through so much, I can't believe it. I've spent the afternoon crying just from the sheer awfulness of it.

"They wanted me to go through all the Tweets again because of their incompetence. Every time I have to go through it it's reliving it all over again."

Ms Criado-Perez received a fresh stream of violent rape threats which she sent to police.

Scotland Yard said officers were trying to contact the campaigner to talk about the case. A spokesman said: "We are now in a position to confirm that the Metropolitan Police Service has not lost any evidence gathered as part of this investigation. The tweets referred to have in fact already been put to a suspect in interview."

A 21-year-old arrested in Manchester, a 25-year-old man questioned by Northumbria Police and a 32-year-old man arrested in Bristol are all due to answer police bail in mid-September.