It only takes 15 to 20 seconds for them to cut through a window or balcony and enter a house.

Nineteen-year-old Rabiul Awal alias Roby is a painter, and knows how to weld window grilles. A short man, Roby takes advantage of his height. He used to cut grilles, squeeze through and enter homes, and open the gate for his fellow robbers to get in.

For this, the gang leader used to give Roby Tk10,000 for every robbery.

Police's detective branch (DB) claimed to have learned all this by interrogating Roby and five other robbers, who were arrested on Monday from the capital's Mohammadpur area.

On Tuesday, these robbers were produced before a Dhaka court, which granted a one-day remand for interrogation.

Interestingly, each of the robbers do different kinds of work during daytime. Some of them are auto-rickshaw drivers, some vegetable traders, while others worked for online food-delivery services.

During daytime, they used to observe the capital's outskirts, like Savar and Keraniganj, and at night, they robbed places using local firearms.

A high-official of DB, involved with the investigation, said during interrogation, they came to know that arrestee Md Sujon Howlader, an auto-rickshaw driver, used to manage the firearms.

"We have come to know that the gang collects each firearm for Tk 12,000 from a person named Rubel. We are now conducting drives to seize the firearms and arrest the supplier," said the officer.

Arrestee Ekram Ali, also an auto-rickshaw driver, mainly took robbers to the target location. Among other arrestees -- Md Babu and Md Rony -- who worked in grocery shops and kitchen markets, used to gather information from locals, said investigators.

Sources said that all robberies were conducted under the leadership of one Md Saddam, who has not been caught yet.

No matter what the gang found in a robbery, Saddam would give each member at least Tk 10,000. If a robbery went wrong, Saddam gave them Tk 5,000, said the official, quoting the arrestees.

For supplying arms and taking robbers to the spot, Saddam used to pay Tk 15,000 each to Sujon and Ekram, said the official.

Shahdat Hossain Sumon, additional deputy commissioner of DB, told The Daily Star yesterday that they had some information about the gang's absconding members and are conducting drives to arrest them.

"We have so far found that Saddam is the ringleader, but there might be another mastermind behind these robberies. We will be able to find more information after investigating further," he added.