proenzaschouler_jackmccollough.jpgWoah as if all the drama surrounding Azzedine Alaïa wasn't enough, things at the Met Costume Institute Gala after-party got a little ugly when one designer was left with a broken nose.

Apparently a fight erupted between Kiefer Sutherland and Proenza Schouler's Jack McCollough (pictured), resulting in Kiefer headbutting Jack and landing him in hospital with a broken schnoz. It all happened while guests including Mary-Kate Olsen and Kirsten Dunst watched on.

The alleged incident occurred because Kiefer was believed to be defending the honour of Brooke Shields, after McCollough knocked her over.

Witnesses said Sutherland demanded McCollough apologise, and when the designer pushed him, he headbutted him in the face.

However, a rep for Shields claims "nothing happened to her," adding "Jack did nothing inappropriate. It's not clear what caused Keifer to do what he did."

A police report was taken and will now be investigated. Unfortunately for the 24 star, he is currently on probation in L.A. for a DUI. Shields is due to be questioned by police regarding the incident today.

Lesson learnt: Nobody mess with 24's Jack Bauer - yikes!

[Source: Guest of a Guest / TMZ / Photo:]