Bank security has improved substantially over the years, but it seems criminals are always one step ahead — especially here in China.

The latest case involves a criminal ring from Taiwan that was able to steal the confidential financial information of 168 people in Xi’an. Using the info, the criminals were able to loot RMB 4.7 million from their bank accounts, reports CCTV 13.

The ring installed pinhole cameras and magnetic readers onto the exterior of ATM machines at 14 banks.

These devices blended in so well with the ATM that banking customers didn’t suspect they were being monitored. The device that reads the victim’s card is installed directly in front of the ATM card slot and is not noticeable unless you are really paying attention.

The gadgets would be left in place for hours, with the ring leaders returning later in the day to collect the data. This carried on for five months.

A banking representative said even though they have a command center where they can monitor ATMs remotely, it’s impossible to watch all machines at the same time.

Four people have been arrested.

Here’s the entire CCTV 13 report, and then a shortened version afterwards:

Photos: Information Times, screenshots from CCTV