HALL COUNTY, Ga. -- Officials say a ladder truck is now being investigated after three Hall County firefighters were injured in a training exercise on Tuesday.

According to Hall County Fire Services spokesperson Scott Cagle, the three men were in a bucket on top of a ladder that was extended. There was a mechanical failure and the ladder dropped about 20 feet and then jammed. That sudden stop is what injured the firemen.

Two of the firefighters were life-lighted to Grady Memorial Hospital; the third was taken by ambulance to a hospital in Gainesville, Ga.

All three were said to be alert, conscious and breathing. They were identified as Will Griffin, T.J. Elliot and Stephen Jackson. They were said to be in stable condition with injuries ranging from bruises to broken bones. One of the firefighters had to undergo surgery, but they are all expected to recover.

Engineers are expected to start investigating the ladder truck immediately. The truck will then be returned to a factory in Ohio.