A man arrested on the charge of being involved in burglaries on Wednesday turned out to be one of the

two who had robbed the Ranikuthi house of an 88-year-old man the day before, police said.

Based on his statements during interrogation, his alleged partner was rounded up on Thursday.

Police said one of the two was allegedly on a “round” around the Ranikuthi house when he overheard Amal Chandra Basu talking about Rs 1 lakh with someone. The accused presumed that the money was in the house.

The accused have been identified as Samrat Mandal, 21, and Seleman Gazi, 19, both residents of Ghutiari Sheriff in South 24-Parganas.

The police did not say which one had overheard the conversation.

Mandal and Gazi had allegedly entered Basu’s house by breaking the lock on the terrace door, tied up Basu with a bed sheet and threatened to kill him with a screwdriver and a pair of scissors before laying their hands on Rs 35,000 and gold jewellery in a cupboard.

They allegedly kept demanding Rs 1 lakh from Basu, as if they knew the money was in the house.

The accused had also allegedly taken away two mobile phones, leaving behind the SIM cards, perhaps thinking that the phones could not be tracked without them. One of the stolen phones was later reactivated in Ghutiari Sheriff.

Officers said the accused, as part of their “operation”, used to roam around in residential areas and peep into windows to overhear conversations in the hope that they would help them select their targets.

On Sunday, one of them is said to have overheard Basu advising a neighbour about a fixed deposit of Rs 1 lakh. “The man overheard an incomplete sentence and surmised that the money was in Basu’s house,” the officer said.

Basu, who lives alone in the single-storey house four days a week and with his son and his family in another house in the neighbourhood, has hearing problems and speaks a little loud.

The retired railway official expressed happiness when Metro told him about the arrests.

“He is very brave. We might not have handled the situation the way he did. A little panic or mistake on his part could have ended badly,” son Siddhartha said.

One of the accused was arrested on Wednesday night during a raid by the police to execute pending non-bailable arrest warrants. The city police had that night arrested 265 such people.

One of the men arrested in Bansdroni, on the charge of being involved in burglaries and mobile theft, resembled the sketch of one of the two robbers who had barged into Basu’s house. The sketch was drawn based on descriptions given by the elderly man.

Although it was dark when Basu woke up around 3.30pm on Tuesday and found two strangers in his room, the light that was entering through the open windows was enough for him to see the intruders’ faces.

“The elderly complainant was shown a photograph of the man and he immediately recognised him,” said joint commissioner (crime) Murlidhar Sharma.

“The man confessed to the crime during interrogation and spoke about his partner,” an officer said.

“The duo were in a hurry to wrap up their operation because they wanted to catch the first train towards South 24-Parganas.... We hope to recover the stolen booty from the spot where the duo said they had kept them.”

Shocked at the way the accused had plotted the robbery, an elderly resident of Ranikuthi said: “What happened was extremely scary. This means we can neither talk loudly in our home nor keep the ground-floor windows open. It is also scary that such criminals are roaming around freely.”