The Bidhannagar branch head of a private bank has been arrested for allegedly duping a city couple into investing more than Rs 1 crore in a financial institute the bank official was allegedly running with her husband, police said.

Supti Mukherjee, the accused bank official, had allegedly promised the couple hefty returns on their investment but failed to deliver.

Supti was arrested from her workplace on Wednesday. The police are looking for her husband Sudip Mukherjee.

According to the complaint, Supti had allegedly used her position in the bank to convince the complainants into making the investment.

“Supti Mukherjee and her husband had misused the former’s official position to lure my clients into believing that they were investing their money in a reliable financial institute for lucrative returns. My clients had invested Rs 1 crore and 5 lakh,” said the complainant’s lawyer, Jayanta Narayan Chatterjee.

Complainant Partha Pratim Roy and his wife used to work in England. They had taken voluntary retirement and came back to their south Calcutta home a few years ago.

Roy has told the police that they knew the Mukherjees for a long time and invested in their company in good faith.

“Initially, I had invested a small amount in 2017. After a few months we were told that according to SEBI rules, if the minimum amount of investment could be increased to

Rs 20 lakh a year, there would be higher returns. We then withdrew all our savings and started investing in this (Mukherjees’) financial institute. We paid in cheques,” an officer quoted Roy as saying.

From 2017 to the end of 2018, the Roys had purportedly received interests on the investment as promised, they have apparently told the police. From 2019, the finance company allegedly started defaulting on their payment.

“At times Mukherjee paid the interest in two cheques, both of which bounced,” Roy has apparently told the police. From mid-2019, the Mukherjees apparently became incommunicado.

The police said Roy had told them that he found both offices of the finance company closed — one at Dalhousie and the other in the Shakespeare Sarani area. In February 2020, Roy lodged a complaint with Shakespeare Sarani police station.

Roy’s lawyer said the accused had moved for anticipatory bail by the end of 2020, but the court rejected the application.

“We arrested Supti Mukherjee from her workplace. Her husband was not found at their home or any place nearby. We are looking for the co-accused,” said an officer.