Kiefer Sutherland allegedly headbutted designer Jack McCollough early Tuesday morning when the Proenza Schouler designer interrupted the "24" star's conversation with Brooke Shields, according to multiple reports.
The alleged incident, which was first reported by the NYC nightlife blog Guest of a Guest, occurred at an after party following the Met's Costume Institute Gala at 99 Prince Street, which is part of The Mercer Hotel, a NYPD spokesperson confirmed to Access Hollywood.
Police told Access they are aware of incident and are currently "looking into" the matter.
According to TMZ, McCollough – a friend of Shields' – interrupted a conversation between the actress and Sutherland, causing the "24" star to became agitated. Sutherland allegedly exchanged words with the designer and then reportedly headbutted McCollough.
TMZ reported that witnesses saw Shields knocked to the ground by McCollough, but a rep for the actress told TMZ, "nothing happened to her… Jack did nothing inappropriate. It's not clear what caused Kiefer to do what he did."
According to People, McCollough told police that Sutherland "was drunk and obnoxious and wouldn't back down or be logical," and he "pulled this stupid wrestling move like a teenager" before headbutting him.
People reported that McCollough suffered a minor cut on the nose.
Sutherland and Shields will reportedly speak to police about the incident on Wednesday.
When contacted by Access reps for The Mercer Hotel and designer McCollough could not be reached.
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