The misappropriation of refunds due on customer accounts has been reported to the PSNI by the Department of Finance Land and Property Services division.
The Auditor General, Mr. Kieran Donnelly, revealed the reported irregularity on Friday.
He said: “LPS has commenced its own investigation to establish the full circumstances and the amount involved. The PSNI has been informed. I will report on the outcome in due course.”
A Department of Finance spokesperson said: “The Department can confirm the individual involved in this incident has been dismissed in accordance with NICS procedures.
"LPS has already taken action and put in place controls to mitigate against any reoccurrence. As a police investigation is currently underway it would be inappropriate to comment further”.