PASADENA (CBS) — The 21-year-old son of Playboy founder Hugh Hefner was free on bail Monday after being arrested on suspicion of misdemeanor domestic violence.

Marston Hefner was taken into custody at the Pasadena home he shares with his girlfriend at about 10 p.m. Sunday, Pasadena police Lt. Rick Aversano said. Hefner posted $20,000 bail and was freed about 2 a.m. Monday.

Police were called to Hefner’s home to investigate a report of domestic violence. No one was transported for medical treatment, Aversano said.

Details about Hefner’s girlfriend were not released, but Hefner has been dating 2011 “Playmate of the Year” Clair Sinclair since 2010.

Hefner’s booking photo would not be released, according to Pasadena police.

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