Three Bangladeshis, including a woman and her son, have been arrested here for robbing "rich and literate people" on the pretext of selling them US Dollars, police said on Thursday.

Mohammad Farukh, 36, Salma, 48, and her son Ujjal, 27 — all residents of Madaripur in Bangladesh — were taken into custody from Geeta Colony in east Delhi.

Explaining their modus operandi, Deputy Commissioner of Police Rishipal said the gang would approach potential victims with a US Dollar. 

They operated mostly in malls and other places, targeting the rich and literate looking persons. They had recently robbed a man whom they met at a mall of Rs.80,000. 

Rishipal said the gang would post as illiterates to gain the victim’s confidence. 

They would show him a Dollar and ask: "Sir, can you please tell me what this is? We found it on the ground… Is this of any value?

"They would say they had around 6,000 more such dollars," said the officer.

If the victim fell for their tale, they would negotiate a "deal" to sell him or her all the Dollars in exchange for a meagre amount of Indian currency. 

The accused would plead that they were in dire need of money. 

"Some victims agreed to buy the 6,000 Dollar bills," the officer said.

"The gang would then woo the victim to an isolated place to exchange the currency. Instead, they would rob the victims, taking away their money and valuables at gun or knife point."