Retired American football star Darren Sharper has pleaded not guilty to allegations he drugged and then raped two women in Los Angeles as part of an ongoing investigation.

The 38-year-old former Green Bay Packers and New Orleans Saints star has been charged with seven rape and drug counts involving four women he allegedly met at a West Hollywood nightclub.

Court documents filed last week (ends14Feb14) revealed additional allegations from women in Las Vegas, New Orleans and Tempe, Arizona.

In court on Thursday (20Feb14), prosecutors revealed a new allegation against Sharper was being investigated in New Orleans, and Miami, Florida police are also investigating one there.

Sharper's bail has been increased to $1 million (Gbp625,000). He posted that amount before leaving court.

If convicted, Sharper faces more than 30 years behind bars.

Speaking outside court last week, the sportsman's attorney Blair Berk insisted her client was innocent, stating, "We look forward to the true facts being revealed in this case, and we are hopeful that Mr. Sharper will be fully exonerated before this case is concluded."

The allegations have cost Sharper his job as an analyst for the NFL Network - he has been suspended without pay.