Jailed gangster Lawrence Bishnoi has been interrogated over a threat letter found outside actor Salman Khan's Mumbai house, sources said. The letter mentions the names of Mr Khan and his father, veteran actor Salim Khan. It threatens the two saying soon they would become Sidhu Moose Wala, the Punjabi singer who was shot dead in his car last month. Canada-based gangster Goldy Brar has claimed responsibility for the murder in a Facebook post.