CelebSpice

Mischa Barton sparked a fight at a Halloween party.

The former 'O.C.' star was left furious when a reveller threw a drink over her at New York's Park Bar on Saturday (31.10.09) after she accidentally stepped on his foot, throwing her own beverage at the unnamed partygoer in retaliation.

An onlooker said: "I was standing beside this guy at the bar when Mischa went past us carrying two drinks.

"The next thing I knew he threw his drink over her back and she turned around and asked him: 'Did you just throw a drink over me?'

"The man responded that the drink was in retaliation for Mischa stepping on his shoe and she threw one of her drinks in his face."

The incident took an ugly turn when the actress - who was dressed as a peacock - returned to her table and told her friends, who rushed to confront the man.