LATEST: CSI: CRIME SCENE INVESTIGATION star William Petersen pulled out of Sunday's (18SEP05) Emmy Awards when his nephew, NICHOLAS, was killed in a motorcycle crash.

Mystery surrounded the actor's last-minute decision not to attend the TV awards in Hollywood, but now sources reveal Petersen was in mourning.

Petersen's nephew had just married his longtime girlfriend AMANDA when he was involved in the accident.

The actor has been given time off from his hit crime drama while he mourns the loss of his nephew.