http://www.people.com/article/prison-escapees-likely-had-help-female-worker-investigators
""Just from the video that I saw, I just don't think they cut the pipes with a sawzall," says Gilliam, CEO and founder of United States Continued Service, a consulting firm.
"When you look at the video of the cuts that were made in the pipes, you cannot do that with a sawzall, which leaves jagged edges," he says. "Those were clean cuts. It looked like they used a plasma cutter or an acetylene torch. You can't make those types of clean cuts with the tools they reportedly had – a drill and a sawzall." "
if I find the source again which mentions the hammer I will post that as well.
The cuts look like the were made by a cut-off wheel.