HONOLULU -- Authorities arrested an Internet predator who was allowed to be free pending appeal after having sex with a high school student.

Robert John McKnight Jr., 37, was sentenced to a year in prison for arranging to meet who he thought was a 15-year-old girl he met online. The girl was actually an undercover officer.

McKnight was free pending appeal, but he violated his bail terms by having sex with an 18-year-old girl he met online, authorities said.

The judge ordered him to begin serving his one-year sentence immediately.