The threatening email that actor Salman Khan received on March 18 was sent by notorious gangster Goldy Brar, who carried out the murder of Punjabi singer and Congress leader Sidhu Moose Wala in May last year, said Mumbai Police on Wednesday.The gangster is currently hiding in the UK, according to Mumbai Police. Mumbai Police took the help of Interpol in the case. They also sent a Letter of Request (LR) to the UK Government (concerned department) regarding Goldy Brar.