According to police, K Ramachandran, a 72-year-old resident of Jalnidhi society in suburban Goregaon, was taking a morning walk on Link Road at about 8 am when he was intercepted by a man in plain clothes claiming to be a policeman.
The "fake policeman" told the victim that the latter was called by his "senior", who was standing near a motorcycle close by, with two more persons.
The four told Ramachandran that there was an incident of murder ahead and he should not walk towards that side.
Later, they advised him to remove all his valuables including gold chain, ring and bracelet, collectively worth Rs 1.17 lakh, and keep it in his pocket, police said.
On the pretext of helping the victim, the accused removed all the valuables from the victim's body, police added.
"They tricked the elderly man and kept a stone wrapped in a paper in his pocket, while stealing the valuables. After the four left, Ramchandran opened it thinking that gold valuables were wrapped in the paper, but he found a small stone," said assistant inspector Sanjay Patil at Bangur Nagar police station.
"We have registered a case under sections 420 (cheating) and 170 (impersonating a government servant) and 34 ( Acts done by several persons in furtherance of common intention) of the IPC against the accused. We also have their descriptions," the officer added.