The MP said he was stepping down temporarily while he defended a High Court action against him. But as our political correspondent Phil Hornby reports, it is thought that Mr Hancock jumped - before he was pushed.
A disciplinary meeting at which the Liberal Democrats have been questioning Portsmouth South MP Mike Hancock has finished. The hearing concerned allegations that the Hampshire politician had an inappropriate relationship with a female constituent.
The 66-year-old denies the allegations. The meeting is finished, but the Liberal Democrats say they are not releasing any further details at this stage.
One of the South's MPs faces losing the party whip over allegations of sexual assault. Portsmouth South's Mike Hancock strenuously denies them but will face the Lib Dem leader today at a disciplinary meeting. Nick Clegg has admitted his party is considering suspending Mr Hancock.