AUSTIN, Texas -- A security breach is prompting Austin officials to re-key more than 6,000 lock boxes.

Another 17,500 remain compromised but will not be re-keyed for another year or two, an Austin official said in a memo to the Mayor and City Council.

Manor Police are investigating a man who had a copy of a special key first responders use to access businesses and apartment complexes across the Austin area.

"That could be anything from a home improvement store to a retail strip center to a high rise building," Austin Fire Marshal Rob Vires said.

MORE | Memo on Knox Box Security Breach

It's the first breach since Austin adopted the Knox Box system 34 years ago. The city's looking to Phoenix, Seattle and Anchorage, which have also had to re-key their entire systems. In the meantime, Arellano said the city's offering to remove keys from Knox Boxes at a business' request until the lock cylinders are changed.

"This means that emergency responders may not have easy access to their building," he said. "In those instances, AFD and Austin-Travis County EMS will still be able to provide full fire and medical response in an emergency."

"We have looked at different options and seen what has been done in the past and try to learn from those as we find what best fits our situation moving forward," Vires said.

Re-keying the entire system will cost almost $2 million. Currently, AFD is focused on replacing locks on Knox Boxes that contain keys to access buildings.

Security gates and other secondary security systems will be replaced in the next two years, upon funding by the Austin City Council. Vires said the new system will also have wireless technology to ensure the master keys are more secure aboard first response vehicles.