Image copyright AP Image caption Cosby has called all the allegations against him "fantastical"

Bill Cosby is counter-suing the woman accusing him of sexual assault when she was 15, claiming she attempted to extort money from him.

The legal action alleges Judith Huth's lawyer approached Mr Cosby's representatives demanding $250,000 (£159,510) to stop her filing claims.

It also says the woman tried to sell her story to a newspaper 10 years ago.

In recent weeks, more than a dozen women have alleged that Cosby drugged them and sexually assaulted them.

Ms Huth alleges that in 1974 she was given alcohol and then forced to perform a sex act on Mr Cosby while at the Playboy Mansion.

She is seeking unspecified damages for "psychological damage and mental anguish", which she says have only recently been linked to the incident, which would extend the statute of limitations.

Mr Cosby's lawyer, Martin Singer, has filed papers claiming Ms Huth's lawyer, Marc S Strecker, approached him demanding $100,000 (£64,000), which was then raised to $250,000, to prevent the legal case going forward.

The comedian is now seeking $33,000 (£21,000) for legal fees from Ms Huth and Mr Strecker.

The court filing insists the "claims are absolutely false" and says that a psychologist has not supplied relevant certification about the psychological effects being newly discovered.

Honorary title revoked

The Los Angeles Police has said it will investigate any reports of abuse against Mr Cosby, irrespective of whether the statute of limitations had passed for prosecution.

"We don't turn people away because things are out of statute. You come to us, especially with a sexual allegation, we will work with you,'' Police Chief Charlie Beck told the Los Angeles Times. "We address these things seriously - and it's not just because it's Mr Cosby.''

The star, 77, is facing a series of allegations dating back to the 1970s.

The accusations, which he has called "unsubstantiated", "fantastical" and "uncorroborated", have led to his stand-up tour being called off and the cancellation of a number of TV projects.

On Thursday, the US Navy revoked his honorary title, claiming allegations of sexual abuse against him were in conflict with its core values.

The honorary title of chief petty officer was bestowed on Cosby in 2011.

He enlisted in 1956 and served four years as a hospital corpsman before being honourably discharged in 1960 as a 3rd Class Petty Officer.