Law enforcement sources tell TMZ Hayden Panettiere's dad, Alan, has been arrested for allegedly battering his wife -- Hayden's mom.

Sgt. Wolf of the Los Angeles Sheriff's Department tells TMZ Alan Panettiere was arrested this morning on a felony count of domestic violence. He was popped after allegedly striking Lesley Panettiere in the face at around 3:00 AM today.

He is currently being held on $50,000 bail.