Shukla was best known as the winner of the 13th season of hit reality TV show Bigg Boss, and as the lead actor in the Indian drama series Balika Vadhu.
A doctor at Mumbai’s Cooper Hospital confirmed the actor’s death to The Indian Express newspaper.
Shukla’s post-mortem examination has not begun yet, as police procedures are still ongoing, the paper reported.
Shukla is survived by his mother and two sisters.
Following the news, tributes began pouring in from fellow stars, fans and public figures in India.
The Family Man actor Manoj Bajpayee wrote on Twitter: “OMG!!! This is So Shocking!!! Words will fail to describe the shock and sense of loss of his near and dear ones !!! May he rest in peace !!! No yaar!!!!”
Indian cricketer Virender Sehwag wrote: “Another reminder of how fragile life is. Heartfelt condolences to #SiddharthShukla ‘s family and friends. Om Shanti”
Indian filmmaker Ashoke Pandit posted a special video as a tribute to the late actor with the caption: “I pay my Condolences to the family of actor #SiddharthShukla who died at the age of 40 due to heart attack. His demise is a great loss to the entertainment industry. Gone too soon.”
“It is true. But I still can’t believe he is no more. Gone too soon… my sincere prayers and condolences to his family, loved ones, and his fans. may his soul rest in peace,” singer Armaan Malik wrote.
Actor Tisca Chopra who was Shukla’s neighbour, wrote: “Numb.. Siddharth, neighbour and occasional walking buddy .. #SiddharthShukla RIP .. hope aunty and friends have the strength to bear your immense loss.”
“Shocked beyond words!! Gone toooooo soon…. Condolences to his family, loved ones. - He was loved by millions,” actor Riteish Deshmukh added.
Shukla made his acting debut with the TV show Babul Ka Aangann Chootey Na in 2008, before gaining prominance with his performance in Balika Vadhu on Colors TV.
He appeared in several reality shows, including Khatron Ke Khiladi, India’s Got Talent and Bigg Boss — the Indian version of Big Brother.
Shukla also starred in Karan Johar-produced 2014 Bollywood film Humpty Sharma Ki Dulhaniya, starring actors Alia Bhatt and Varun Dhawan. He was last seen in the third season of Ekta Kapoor’s Indian webseries Broken But Beautiful, which premiered on local streaming platform MX Player.
He had recently announced his involvement in the forthcoming film Silsila SidNaaz Ka with model and actress Shehnaaz Gill.
Local media reports suggested that Gill left an ongoing shoot when she heard of Shukla’s passing.
The Balika Vadhu actor had a large social media following, including on Twitter and Instagram. His last post on Twitter was a congratulatory message for Indian Olympic gold medalist Neeraj Chopra.
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