MP Simon Danczuk in legal row over Cyril Smith abuse email
Labour MP Simon Danczuk has been threatened with legal action over claims his office accused a former council leader of covering up child abuse allegations against Cyril Smith.
Colin Lambert claims he was smeared by Mr Danczuk's office in an email which said he deliberately covered up a scandal involving the former Rochdale MP.
Mr Danczuk has denied any wrongdoing.
Last June, Mr Lambert was forced out as leader of Rochdale Council.
He believes Mr Danczuk, the current Rochdale MP, orchestrated a concerted campaign to oust him.
"It's more than nasty - it's personal," Mr Lambert told the BBC.
"It's libellous that he is accusing me directly of being involved in a plot 10 years earlier to cover up Cyril Smith's abuse, which is outrageous."
A book co-authored by Mr Danczuk and his former senior parliamentary aide Matt Baker investigated claims former Rochdale MP Smith, who died in 2010, abused vulnerable young boys in the town.
An email, dated November 2012 and apparently sent from Mr Baker's address, accused Mr Lambert of deliberately covering up the scandal.
Local businessman Paul Turner-Mitchell, who claimed to be a close friend of Mr Baker, said he was asked to leak the message.
"I was asked to leak it to the local media with the intent, I assume, to report it and to embarrass local [Labour Party] members," Mr Turner-Mitchell said.
Mr Baker said his former associate was acting maliciously after they fell out and said he had reported him to the police.
The BBC has seen no evidence Mr Danczuk knew about the email.
Mr Danczuk said: "I'd suggest they don't waste their money because they are not going to get anywhere in terms of legal action".
"I haven't done anything wrong, my office hasn't done anything wrong.
"There's no case to answer. It's as simple as that.
"If he believed that evidence at the time he should have gone straight to the police and the council and demanded action."
Mr Lambert said he planned to start legal action against the MP and Mr Baker early next week.