Former "Baywatch" actor Michael Bergin (search), who said he had an affair with John F. Kennedy Jr.'s wife less than a year after she was married, was charged Tuesday with felony driving under the influence.

Bergin, who wrote a book about his relationship with Carolyn Bessette Kennedy (search), was charged in connection with a July incident in West Hollywood in which a professional roller blader was struck and seriously injured by a car.

Bergin is free on $50,000 bail. He has an unlisted phone number and could not be reached.

The roller blader, Jennifer Armstrong (search), was allegedly hit by Bergin's SUV shortly after 11 p.m. on July 16. The woman suffered fractures to her left leg, according to district attorney's spokeswoman Sandi Gibbons.

Bergin was charged with one felony count of DUI causing injury and one misdemeanor count of driving with a blood alcohol level of more than the legal limit of .08 percent. Both counts alleged great bodily injury to the victim.

Bergin's book, "The Other Man: A Love Story," (searchwas released in March.

The longtime friend of Carolyn Bessette said his affair with her as a married woman began in Los Angeles in 1997, when she spent 11 days with him after saying Kennedy was on a kayaking trip with his friends.