Pickpockets seem to have discovered a novel method to dispose off stolen wallets which have identification cards in them.
In the last six months, the Chennai postal department has found 70 such wallets inside mail boxes.
Pickpockets just drop off the wallets after taking the money, a senior official in the city's postal department said.
ID cards such as Aadhaar, PAN and driving licences have been found inside the wallets.
"The sub-postmasters in the post office concerned take extra pains to ensure the cards are returned to the people to whom they belong. Even though there is no income to the department (from this activity), they do it as a service to the citizens," the official said.
In case there is a contact number written on the ID cards, the staff ask the people concerned to pick up their wallets from the post office.
If no number is available, they put the ID cards in an envelope and dispatch it to the address provided.
Recently, some passports were also found inside the mail boxes. They were handed over to the Regional Passport Office, the official said.