Harendra Badhai, a former government doctor, was staying with his younger brother Harish Badhai (55) at their Shastri Nagar residence, police said, adding, the brothers were suffering from mental ailments.
The neighbours informed the police about a foul smell emanating from the house, following which police found Harendra's rotten body yesterday, they said.
The younger brother who was also present in the house said that Harendra is sleeping and asked the police not to take Harendra's body, police said, adding, he (Harish) was holed up inside his residence with the body for nearly one month.
According to preliminary investigation, the brothers had confined themselves to their house and the death could be a result of hunger.
The tiffin service which used to deliver them their food had also not come for the past 20 days, police said.
The younger brother was an Air Force officer and the elder brother was a doctor at CHC, Sardhana, both of whom left their jobs after mental problems, police added.
The body has been sent for post-mortem and the younger brother has been taken into police custody for further investigation.