VISTA, Calif. -- An Oceanside transit security guard who tried to coerce a woman into performing a sex act on him was sentenced Tuesday to 18 months in state prison.

Terry Charles Ware, 23, pleaded guilty July 28 to attempted oral copulation under the color of authority, false imprisonment and a misdemeanor charge of impersonating a peace officer.

Ware was arrested in the early morning hours of Nov. 17, 2007, after the victim and her male companion flagged down a police officer to report what happened.

According to prosecutors, Ware accosted the couple around 1:40 a.m. in a parking lot at the Oceanside Transit Center in the 300 block of N. Cleveland Street.

Ware put the woman in his security vehicle and told her he could cite her, but "would not write a ticket if she would perform oral sex on him," said Deputy District Attorney Fanny Yu.

The defendant, who was armed at the time, did not have the authority to issue citations, the prosecutor said. It was unclear if he told the woman he was full-fledged law enforcement officer.

Yu said Ware was employed by Heritage Security Co., a private firm that patrols the transit center, but not the parking lot.

Ware -- who faced a maximum of three years and eight months behind bars -- was sentenced by Vista Superior Court Judge Joan Weber.