A feminist campaigner bombarded with rape and death threats on Twitter has accused police of failing to show sensitivity to victims.
Caroline Criado-Perez, from north London, claimed that police lost evidence that she had sent to them.
After they advised her to sift through the abuse she had received to retrieve the evidence, she said she was reduced to tears.
Scotland Yard defended its handling of the "complex and large investigation".
Ms Criado-Perez was subjected to torrents of abuse after campaigning for banknotes to feature notable female historical figures, and not just men.'Sheer awfulness'
She said it was "appalling" that police had asked her to go back through some of the abusive tweets she had received "because of their incompetence".
End Quote Metropolitan Police spokesman
We are urgently trying to contact the complainant so we can discuss with her the issues that she is raising "
"It just shows such insensitivity to someone who's been through so much, I can't believe it," she said.
"I've spent the afternoon crying just from the sheer awfulness of it.
"Every time I have to go through it it's reliving it all over again."
She accused Scotland Yard investigators of failing to understand how to treat victims of online abuse.
Ms Criado-Perez also questioned why only three people had so far been arrested in connection with her case, when she believes a much larger number were involved.'Mindful'
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.
A Scotland Yard spokesman said: "We are urgently trying to contact the complainant so we can discuss with her the issues that she is raising on social network sites, to once again explain our approach and tactics in this investigation to provide both answers for her and clarity.
"A huge amount of evidence, including hundreds of tweets, has been captured by officers and thoroughly examined.
"This has been a complex and large investigation that has involved the examination of hundreds of messages sent on Twitter.
"A number of people have so far been arrested in connection with the complaint, and remain on bail.
"We are mindful of the truly hurtful and distressing impact that receiving such communication can have, however we must be sure to focus our efforts on the things that we and the CPS believe is a crime and can be prosecuted."