CBS Affiliate WPEC correspondent Chuck Weber said two employees of Loomis Fargo & Co were approached by several men after they pulled up to service an ATM.
A sheriff's department spokeswoman said the suspects were black males wearing light clothing and ski masks, and were carrying handguns and an assault rifle.
Shots were exchanged between the armored car driver and the holdup men. Police do not know if any of the thieves were hit.
Most of the suspects left in a light blue van which they later abandoned, along with clothing and masks. Another man who left the scene on his own was apprehended by Sheriff's deputies.
The driver who was shot in the leg right below the knee was driven to the hospital by his partner. Weber said he is going to be OK.
Anyone with information is being asked to contact CRIMESTOPPERS at (800) 458-TIPS.