BALTIMORE -- Two Baltimore area gas stations lost gas and money after thieves got a hold of a master key to reprogram the pumps to steal gas.

The gas station owners said the reprogramming was done in such a way that the transactions didn't register inside the station so the owners had no idea that the gas was gone until they got their weekly totals.

At one of the stations, Riaz Ahmid, the owner, said over 2,800 gallons of gas was stolen costing about $9,000. And at a BP Station on Russell Street, the owner, Majid Hussain, said about 900 gallons was taken valued at about $2,700.

And witnesses said at one of the stations, a person was seen standing at the altered pump collecting money from people.

The owners also had to incur additional costs to change the lock system on the pumps and upgrade their security systems.

Baltimore City police said no one was caught in either case and the owners don't know if it's the same person or people involved. They also said it may be difficult to track down the people responsible for pumping the gas or the people who bought the gas illegally.