Former Liberal MP Sir Cyril Smith, who died in September 2010, has been accused of abusing young boys at Cambridge House hostel in Rochdale during the 1960s.
Simon Danczuk, MP for the area, made the allegations during a statement in the House of Commons this afternoon.
Mr Danczuk told MPs he had been passed statements that were issued to the police in the 1970s making allegations against Sir Cyril Smith.
He said the statements made "grim reading" and urged Greater Manchester Police "to consider re-opening this case".
Lancashire Police, which covered the Rochdale area at the time, responded to say that they believe there was an investigation in the late 1960s but "no records are now held".
Sir Cyril's brother, Norman, told the newspaper:
Sir Cyril was a Liberal MP for Rochdale from 1972-92.
A Liberal Democrat source said all fresh allegations of abuse must be reported to police.