The Maduravoyal police on Monday solved the Tamilnadu Mercantile Bank ATM theft case with the arrest of a bank employee.

Over a dozen persons, including bank staff, were interrogated as part of the investigation into the theft of ₹8 lakh from the ATM on Sunday.

The police said the masked suspect arrived in an autorickshaw at the ATM around 12.30 p.m. Sunday and entered the kiosk on the pretext of spraying disinfectant. The suspect opened the machine and was taking out cash.

A customer, who came to deposit cash, grew suspicious and alerted the security guard. By then, the suspect had left the spot with the booty.

Following a complaint filed by bank manager Rajkumar, Maduravoyal police inspector T. Radhakrishnan took up investigation. Mr. Radhakrishan said: “The CCTV footage and good coordination of our team helped solve the case quickly.”

The police gave the name of the suspect as M. Sivanandan, 39, an employee working with another branch of the bank. The accused knew the password as he regularly loaded cash into the machine. He allegedly stole the money to settle a loan taken to build his house at his native place in Thoothukudi district.