In the five-minute-long video -- believed to be shot by a bystander, policemen can be seen having a hard time getting the man - sporting a yellow tee shirt - inside a police van, and a woman, later identified as Mamta, screaming for help.
Apparently failing to handle the man, one of the policemen can also be seen hitting him twice with his lathi.
Other senior officials maintained that the "unverified" video clip is not clear enough, but it may be considered for further leads, if needed.
On Monday, a 35-year-old man, later identified as Shanu Shahnawaz Chaudhary, who tried to intervene in a road-side scuffle between a couple and the police at northeast Delhi's Nand Nagri area, died in mysterious circumstances.
More From This Section
Chaudhary's wife, Mamta, later alleged that her husband was killed by the policemen.
During investigation, it emerged that Chaudhary was out on parole. He was sent to jail around four months ago in connection with a criminal case.