The police rushed to the location, following which the entire farmhouse was surrounded and all its entry and exit points were blocked.
A 38-year-old businessman was strangled to death allegedly by a group of robbers who first sedated his parents with chloroform and then attacked him at a farmhouse in south Delhi's Chhatarpur area in the early hours on Thursday.
The incident took place around 2.30 am when the accused gained access to the two-storey farmhouse through a window, eluding the security guard deployed at the main gate of the colony and first sedated the elderly couple sleeping on the ground floor, a police official said.
They robbed them of cash and jewellery, after which around three gang members went to the first floor, where they confronted the victim, Rohan Gupta.
They tried to sedate him with chloroform but when he tried to fight back, he was attacked and later one of them strangled him, the official said.
The incident came to light when a neighbour called up the police assuming that a quarrel had broken out in the family.
The police team which rushed to attend the call soon evaluated the actual situation and called for reinforcement, following which the entire farmhouse was surrounded and all its entry and exit points were blocked, the official said.
While five of the accused, identified as Ajay, Vipin, Vinod, Shivnath and Vinod Kumar, were arrested, one of their accomplices is believed to have escaped.
"A case of murder and dacoity has been registered and the five arrested persons are being interrogated," additional DCP (south) Nupur Prasad said.
From preliminary investigation, it emerged that the accused had conducted recce before executing the crime. They had keenly observed the movements of the Guptas but the attack on Rohan was unplanned, an official privy to the investigation said.
The investigators are probing if any of the accused persons were aware of the layout of the farmhouse, had worked there before or known to any of the former domestic help or staff members of the Guptas.
The previous crime record of the gang members are also being scanned, the official added.