A convicted murderer who escaped a Pennsylvania prison last week was filmed climbing between two walls to reach the facilitys rooftop, a tactic that was used by another inmate at the same prison earlier this year.

Surveillance video released Wednesday shows Danelo Cavalcante, 34, carefully positioning himself between the walls in a Chester County Prison exercise yard with his body stretched horizontally, so that his hands reach one wall and his feet the other. He then scales the walled passage, vanishing out of sight.

A tower guard, who is now on administrative leave, failed to see Cavalcante as he made his way through razor wire and out of the prison Thursday. It wasnt until about an hour later that he was discovered missing during an inmate count, according to Howard Holland, the acting prison warden.

While we believed our security measures we had in place were sufficient, they have been proven otherwise, Holland said amid criticism over the similarities between Cavalcantes escape and one in May.

That month, inmate Igor Bolte also scaled two walls in the exercise yard and onto the roof. He was spotted by a guard and captured within five minutes .

After Boltes break, razor wire was added to the exercise yards rooftop to prevent a repeat. Now, following Cavalcantes escape, additional reinforcements will be added, Holland said.