A convicted killer serving life behind bars when he staged a daring escape from a maximum-security prison has pleaded guilty to criminal charges for the breakout.

In 35-year-old David Sweat's second court appearance since his capture in June, he no longer wore a sling from his gunshot injuries, his head was shaved and he politely answered a series of questions from the judge.

Sweat has been in solitary confinement at Five Points prison.

He pleaded guilty to two felony counts of first-degree escape and a felony count of promoting prison contraband for possessing hacksaw blades used to cut his way out.

He escaped June 6 from Clinton Correctional Facility with Richard Matt, another convicted killer. Matt was shot dead June 26.

Sweat was shot and captured two days later.