Actor Bill Cosby speaks at the National Action Network's 20th annual Keepers of the Dream Awards gala in New York April 6, 2011. REUTERS/Lucas Jackson

(Reuters) – Pennsylvania prosecutors said on Wednesday that comedian Bill Cosby has been charged with sexual assault in connection with an incident in 2004.

An arrest warrant has been issued for the comedian for allegedly drugging and sexually assaulting a woman at his Philadelphia-area mansion in January 2004.

The Montgomery County District Attorney’s Office said at a press conference that new information came to light this year in the case.

More than 50 women have come forward with claims that Cosby had drugged, and in numerous cases, sexually assaulted them in incidents dating back decades.

Cosby, 78, has repeatedly denied wrongdoing and had never been criminally charged. Many of the alleged incidents occurred decades ago and the statute of limitations for prosecuting them expired long ago.