Whitmore declined to name the woman that Panettiere is accused of hitting, but said she reported to deputies that he struck the woman three times with an open hand.
Whitmore said detectives would not release a mug shot of Panettiere.
Los Angeles court records do not indicate any prior charges for the 49-year-old father of Hayden Panettiere, who plays Claire Bennett on NBC's hit show, "Heroes."
Michelle Bega, Hayden Panettiere's publicist, said the arrest was a "private matter" and said the actress would have no comment.
