Allegations of sexual abuse have been made against Sir Cyril Smith in a new book by the Labour MP for Rochdale, Simon Danczuk.
Sir Cyril was previously a Liberal Democrat MP for the same constituency, and allegedly raped boys at Knowl View residential school and abused boys at the privately run Cambridge House children's care home.
Liberal Democrat President Tim Farron said the party needs to answer "serious questions" about who knew Sir Cyril faced allegations of sexual abuse.
Liberal Democrat leader Nick Clegg last year said the allegations against Sir Cyril should be investigated "to the bitter end".
More top news
An attacker armed with a machete killed a woman and wounded two others in the southern German city, according to reports.
A swimmer has gone missing and two others were rescued by the coast guard after they got into trouble in the sea at Camber Sands.
Hundreds joined the party for Jerika Bolen, 14, who has decided to come off life support and allow herself to die later this year.