LIRR riders’ bank and credit information may have been under surveillance by thieves.

MTA police located hidden cameras at seven ticket machines — and are asking riders to check to see if there has been unauthorized activity on their accounts, according to authorities.

The cameras were on the underside of a black metal strip, which was put across the top of the machine with adhesive.

MTA Police Chief Michael Coan said they looked like they were part of the machine.

The machines with cameras were at the Great Neck, Bayside, Greenvale, and Merillon Avenue stations.

Tipsters with information about people acting suspiciously at the machines or tampering with them are asked to call 1.718.361.2247.