The Indiana Department of Transportation says a breach in security affects 4-thousand employees.
In a letter to employees, in-dot explained that names and security numbers were accidentally posted on an internal network drive.
It is urging them to put a fraud alert on their credit files.
In-dot commissioner Karl Browning said the information was posted sometime between September 6th and December 4th.
That file was available to all employees, and also some third parties.