Two men, one of them a teenager, have been arrested for allegedly duping people with false promises of supplying oxygen cylinders against money.

Calcutta police have zeroed in on the duo, who were operating separately, by tracking the bank accounts where they had asked the complainants to transfer the money for the cylinders that the complainants urgently needed for their Covid-affected family members or relatives.

The police identified the accused men as Rupam Saha, 19, and Pramit Bhattacharjee, 29, both residents of North 24-Parganas.

“Both are unemployed and had picked up their targets from social media posts. Both had the same modus operandi. They had asked the complainants to transfer the money online against false promises of supplying them with the cylinders later, which they never did,” said a senior officer in the detective department that is dealing with these complaints.

Calcutta police have published a helpline number (9874909640) and an e-mail id (jtcpcrime@kolkatapolice.gov.in ) to report frauds on oxygen cylinders, plasma, arranging beds in hospitals and arranging medicines required for Covid-19 treatment.

Both arrests were made after receiving complaints through either the e-mail id or the helpline.

Police investigations have found the involvement of multiple gangs from Bihar in such frauds. No one from the Bihar gangs have been arrested till Saturday evening.

Senior police officers said people who post their urgent needs on social media are most vulnerable to such frauds.

“It is obvious that if someone is in urgent need to save a life, he or she will not think twice before transferring money if that helps them get the urgent service they are looking for. The fraudsters are taking advantage of this desperation,” said the officer.