Indian authorities on Monday tightened the security for Bollywood superstar Salman Khan's and his father Salim Khan after the two allegedly received death threats.

"The security for the Khan family has been beefed up in the wake of a threat letter the Khans received on Sunday," a senior officer of Mumbai Police told the local media, after he visited Salman's house this morning.

In fact, Salman's father spotted the "threat letter" outside the family's house at Bandra Bandstand promenade in a posh Mumbai locality during his morning walk on Sunday.

"You will meet the same fate as Punjabi singer Sidhu Moose Wala," the letter stated.

The popular singer was recently shot dead by assailants in the state of Punjab after the local authorities reduced his security cover.

Police said they were taking the threat letter seriously as the Punjabi singer was killed by suspected members of infamous Lawrence Bishnoi gang that threatened to eliminate Salman Khan in 2018.

Born as Abdul Rashid Salim Salman Khan in December 1965, the superstar has acted in over 80 films in his 33-year-long career. He is the third-richest Bollywood actor, with an estimated net worth of USD 360 million.

Apart from playing a range of popular roles from a romantic hero to a flashy action star, Salman is also a film producer.

Salman began his career in Bollywood in 1988, with a supporting role in Biwi Ho To Aisi. But his real success came a year later after his award-winning performance in romantic blockbuster Maine Pyar Kiya.

Action thriller Karan Arjun (1995), comedy film Biwi No 1 (1999) and the family drama Hum Saath-Saath Hain (1999) were his other commercial hits.

After a brief decline in his career graph in the 2000s, Salman got greater stardom in next decade by playing the lead role in action films like Dabangg (2010), Ek Tha Tiger (2012), Kick (2014) and Sultan (2016).

The 55-year-old is also a television presenter and runs a charity, Being Human Foundation.

But the bachelor has a dark side too -- one of his former girlfriends accused him of abusing her, and he was sentenced to five years imprisonment in 2018 for killing two black bucks, a protected antelope species, on a hunting trip. He is currently out on bail.