Gangster Lawrence Bishnoi has denied any role behind a threat letter sent to actor Salman Khan and his father and screenwriter Salim Khan, sources in Delhi Police have said. The gangster, who is in Tihar jail and has been under the spotlight since Punjabi singer Sidhu Moose Wala's gruesome murder, has told police during questioning that he has no clue regarding the threat to the actor, the sources added.