Deputy Labour leader Harriet Harman has been forced to change the password on her Twitter account after it was hacked, she told MPs today.
Ms Harman did not say what was in the "bogus Tweet" on the microblogging website but said: "I wouldn't ever send a Tweet like that."
The admission came as Labour former minister Janet Anderson urged the Government to look into an array of "fake" Twitter accounts in the names of all north-west MPs.
During Commons exchanges on upcoming parliamentary business, Commons Leader Ms Harman said there was a "real problem here" and promised to "see what Government ministers might be able to do about this".
She added: "In fact my own Tweet account was hacked into this week - the hon lady doesn't know this, this is not a planted question - and a Tweet was purportedly sent by me widely, which I can assure everyone was not from me.
"And I actually got a response to that bogus Tweet from the former shadow leader of the House who's now the (shadow) prisons minister (Tory Alan Duncan).
"I've got to get back to him and tell him it wasn't from me - I wouldn't ever send a Tweet like that."
Ms Harman later wrote on her Twitter page: "Last tweet genuinely from me was about Commons reform. Now changed password."
There was no evidence of the bogus message on either her page or that of Mr Duncan.
In the Commons, Ms Anderson (Rossendale and Darwen) pointed to a site called "MP Tweets", which she said had been set up by a group named The Year of Collaboration.
She told MPs: "This has set up an individual Twitter account in the names of every MP in the north-west.
"So we now have a situation where our constituents believe they are twittering with us and communicating with us, when in fact we have nothing whatsoever to do with these sites."
Twitter allows its users to write messages of up to 140 characters which are posted on their profile page and sent to their followers.Reuse content