A chilling video of the incident shows the groom clutching his chest as a firearm goes off, and eventually collapsing.
The video, shot by the wedding photographer, also captured the exact moment when the pistol was fired.
While the groom, 24-year-old Sunil Verma was sitting for his wedding rituals on Saturday, a man wearing an orange shirt is seen handling a pistol in the background when it is fired.
Mr Verma suddenly presses his hands to his chest before collapsing, as clueless wedding guests watched on.
The incident occurred in Lakhimpur Kheri district of the north Indian state of Uttar Pradesh.
The guests present at the time of the incident reportedly did not realise what had happened because of loud music playing at the time.
WARNING- This video contains content that some viewers may find distressing
Mr Verma, who worked as a medical supplies salesman, was immediately rushed to a hospital where doctors pronounced him dead.
The man who is seen holding the weapon in the video has been identified as Ram Chandra, a close friend of the deceased groom, who is said to be on the run from the police after being charged with murder.
“We have booked Ram Chandra under section 302 (murder) of IPC. He has been absconding since the incident and will be arrested soon. We received a complaint that Sunil Verma died in celebratory firing. We are investigating other angles as well,” a police officer told The Times of India.
Police are also investigating whether the accused fired the weapon deliberately.
Although it's prohibited under Indian law, it’s not uncommon to see relatives and friends of the groom or the bride firing weapons into the air at wedding celebrations.
There have been several incidents when shots fired have accidentally killed bystanders.
In February, a groom died in a similar incident on the day of his wedding because of celebratory firing by a guest.
It is more prevalent in states of Punjab, Uttar Pradesh, Bihar, Haryana and Delhi. The state high court of Uttar Pradesh recently directed the state government to ensure effective enforcement of the law against celebratory firing.
In some states, police have been given powers to charge anyone accused of causing death by celebratory firing with murder, instead of a lesser charge of culpable homicide, not amounting to murder.
