LOS ANGELES (CBS) — Paris Hilton’s younger brother, Conrad, was arrested Friday for a probation violation involving marijuana, according to TMZ.com.

The socialite’s 18-year-old brother was arrested around noon after he tested positive for marijuana.

TMZ.com reported the positive test violated Hilton’s probation from an earlier marijuana arrest.

He was held at a juvenile hall in downtown Los Angeles before being released more than an hour later, according to the sheriff’s Inmate Information Center.

(©2012 CBS Local Media, a division of CBS Radio Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. Wire services contributed to this report.)