Roman Polanski

Swiss officials received a formal request to extradite film director Roman Polanski to the United States to face charges he had sex with an underage girl.

Polanski, 76, has been on the run from U.S. authorities since 1978 after he pleaded guilty to having sex with a 13-year-old girl. He could be sentenced to two years in prison on the charge.

He was arrested Sept. 26 while traveling to Switzerland to receive an award at a film festival and has been trying to win release since. Friday's announcement of a request for extradition is likely to set off another series of legal challenges so it is unclear when -- or if -- Polanski would be sent to the United States.

Polanski in 1977 was indicted on several felony counts, including rape by the use of drugs and child molestation. Authorities were investigating allegations Polanski gave a 13-year-old girl champagne and Quaaludes and then had sex with her.

He pleaded guilty to "unlawful sexual intercourse" and was sentenced to a 90-day psychiatric evaluation at a prison but was released after about half that time. After a judge ordered Polanski back into the program, the director left the United States on Feb. 1, 1978.