Body of Jitendra Mann (27), who was working as a trainer at a gym at sector Alpha here, was found by his boss Pritam Tokas, Superintendent of Police (Rural) Suniti Singh said.
On January 10, he went to the gym in the morning but since then his mobile phone was switched off, she said.
On failing to contact him, Tokas, who had a key of Mann's apartment, reached there and opened the house. He found Mann's body lying in a pool of blood with bullet wounds, Singh said.
Tokas informed police who reached the spot and sent the body for post-mortem, the SP said.
Mann's father Satya Prakash and mother Rajbala lives in Delhi, she said.
In 2008, Mann had registered himself as a boxer with Haryana State Boxing. He also used to play for Delhi. He had taken part in several boxing events in France, Uzbekistan, Cuba and Russia. He left boxing several years ago and started working as a gym trainer, Singh said.
He was living alone in Greater Noida for the last few years and shifted to this flat in AVJ heights Apartments four months ago.
Prima facie the assailants locked the door of Mann's house after killing him and had taken away his mobile phone, she said.
Police were trying to identify the assailants through CCTV footage and arrest them, the SP said.