40-year-old dentist Pankaj Narang was beaten to death by a group of about 12 people at his residence in Vikaspuri area on Wednesday night.
Three days after a 40-year-old dentist was allegedly beaten to death by a group of people outside his residence in New Delhi, investigators are looking for CCTV camera footage which may have captured the attack on the doctor.
An official privy to the investigation on Saturday said police have so far obtained one footage which shows a group of around 12 persons moving in a lane in which the victim, Pankaj Narang, was attacked though it does not contain visuals of the assault.
The nine persons, including four juveniles and a middle-aged woman, apprehended so far in connection with the case were identified with the help of the lone footage obtained through one of the premises nearby the victim's house.
Police have also approached some office in the area as the CCTV cameras in their premises are expected to cover the spot where the brutal attack took place, the official said.
Meanwhile, the police are close to identifying three others involved in the attack but their roles are yet to be verified.
They have also roped in the cyber cell wing to track persons who allegedly tried to give a communal colour to the entire incident through social media and other communication channels.
Patrolling in the area has been increased and local residents at a slum, where the accused persons reside, are being questioned to ascertain identities of the others, the official added.
Mr Narang was dragged out of his house and allegedly beaten to death with bats, iron roads and hockey sticks in west Delhi's Vikaspuri area.
According to police, the dentist had taken out his son and nephew to play cricket to celebrate India's victory over Bangladesh in the World T20 match. When they were playing, the cricket ball rolled out on to the road and Mr Narang's eight-year-old son had gone to collect it.
Then, Naseer (23) and a minor, both residents of a nearby slum cluster, sped past on a motorcycle which grazed the child, triggering a scuffle between the doctor and the bike- borne youths.
However, after around 10 minutes, the duo came with around 10 people and dragged Mr Narang from his house and attacked him.