Amol More, 37, an official of the agency that is adjacent to the general store, said: "Two people used to come to the shop for two to three hours a day".
The police said the tunnel led to a shop near the bank.
According to local police, thieves dug a tunnel under the Navi Mumbai bank, broke into 30 lockers and stole valuables worth Rs 5-6 crore.
As the news spread on Monday morning, around 11.30am, a crowd started gathering in front of the bank. The Bank officials were shocked to open the bank only to find the robbery that already happened on Sunday.
"After digging one part of the tunnel, the culprits put plywood on the upper side, which was supported by small bamboo sticks".
An investigation officer said, "The accused had chalked out a detailed plan". Everyone, from those worked at those shops to those who visited it, started jogging their memory for answers on whether they had seen anything suspicious over the past five months. "However, there were none inside the locker room to respect the privacy of customers", said Kiran Patil, assistant commissioner of police (Nerul) division. The burglars knew where exactly the tunnel should be drilled and that there were no CCTVs in the locker room and the type of tools to be used to break the locks. The relationship of customers who avail locker services is that of a lessee (landlord) and lessor (tenant), and the customer is responsible for his or her valuables kept in a locker which is owned by the bank.
The police have formed 10 teams and have sent their officers to different places looking for the criminals.
Senior Police Inspector Suraj Padvi from Sanpada police station said, "Some locker owners are out of the city and couldn't come on Tuesday".