Matt, 48, and Sweat, 34, were in adjoining cells. Using hacksaws, they pried off the grates of the air vents at the backs of their cells. The paint on the walls is so irregular and chipped, it was impossible to tell they had been tampered with, the sources said.
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Then, carrying the tools in a guitar case one of the inmates was allowed to have in his cell, Matt and Sweat shimmied down pipes six floors from catwalk to catwalk until they reached the ground floor.
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At one point, they reached a wall and were able to pass through after knocking out a few bricks. The next wall they hit was the massive prison wall, and there was no going through this.
Holes in the stones suggest that at first they tried to drill through it, sources said. Then they came up with a brilliant Plan B.
Realizing that in the summer the steam pipes arent used, they cut one opening into the 24-inch diameter steel pipe at the base of the wall then cut another opening from inside the pipe on the other side of the wall.
http://www.nydailynews.com/news/national/felons-escaped-n-y-prison-cuomo-article-1.2250257