The man, identified as Kuldeep Dixit, died after being hit by a bullet allegedly fired from his licensed rifle to celebrate his friend, Shiv Prakash's marriage, Superintendent of Police (east), Anurag Arya said.
While the guests were busy dancing, the victim's another friend, Sanjay Maurya, fired several shots in the air to celebrate and a bullet accidentally hit Mr Dixit in the stomach, the police official said.
He was rushed to Kanshiram trauma centre, where he was declared brought dead, Mr Arya added.
After hearing about the incident, top police officers including SSP, Akhilesh Kumar, rushed to the site and arrested Mr Maurya, he added.
The victim hailed from Rae Bareli and was posted in Ambala.