According to the Los Angeles Times, police said the man put Sizemore in a headlock after threatening the actor and the woman with a pretend gun. The alleged attacker then stole Sizemore's guitars and other possessions.
The unidentified man has been charged with grand theft and vandalism, E! News reported.
Often cast in tough-guy roles and action films, Sizemore has starred in "Natural Born Killers," "Saving Private Ryan" and "Black Hawk Down."
2014: The Year in Music [PHOTOS]