'CSI' star Marg Helgenberger has criticised Justin Bieber's behaviour during his two guest stints on the series, describing him as "a brat".
Helgenberger, who plays Catherine Willows on the drama, made the comments during an interview on a French radio station this weekend, when asked how the cast had responded to the Canadian popstar's involvement.
According to TMZ, the actress said: "Justin Bieber wasn't bad.
"He had never acted before."
However, when pressed, Helgenberger admitted that he had often acted childishly during working hours.
She added: "I shouldn't be saying this, but he was kind of a brat [on the set].
"He was very nice to me, but he locked one of the producers in a closet, and he put his fist through a cake that was on the actors' table."
Bieber made two guest appearances on CSI as teenage bomb expert Jason McCann, before his character was dramatically killed off in February.
