Santacruz residents alert activists after Ronak Agarwal, 25, started a daily routine of sitting naked by the window, passing obscene remarks.Social activists on Friday afternoon rescued a scion of a prominent builder family from a small filthy room in Santacruz (W) where he had been confined for three years, according to the police.Ronak Agarwal, 25, is said to be suffering from a mental condition. His family, owners of Agarwal Developers, shifted him from their Khar apartment to the one-room house on a construction site after apparently finding him to be a danger to others.Residents of the Santacruz locality approached an NGO recently after Ronak started a daily routine of sitting naked next to the window and making obscene gestures at passersby.Activist Akil Chitle said following the complaints, he decided to check out the house before alerting the police. He peeked inside and found Ronak living in appalling conditions — garbage was strewn all over the floor and Ronak barely had any clothes.The Agarwal family had hired a caretaker who did not let Ronak leave the room or allow anyone to enter. Ronak’s mother brought him food every day.“The door was locked from outside. We called the Santacruz police who rescued the man [Ronak],” Chitle said, adding that Ronak stretched his hand through the window the first time he saw him.Ronak’s parents were summoned to the police station and ordered to get him admitted to a hospital immediately.When Mirror contacted the father, Vijay Agarwal, he admitted that the family had kept Ronak there. “I have all the supporting documents and will be producing it before the police,” he said, but refused to elaborate.According to the police, Ronak had met with an accident when he was 19 years old. The incident left him mentally unstable.Chitle said that there was an overpowering stench from the one-room house where Ronak was locked up. “The conditions were inhumane. He was not wearing any clothes and could not understand anything we said to him,” Chitle said.AssistantInspector Sanjay Mali of the Santacruz police station said that they would verify the family’s claim that Ronak was mentally unstable. “We have asked his parents not to confine him to the room, and to admit him to a hospital,” the officer said.