The upstate New York prison guard who was sentenced to up to seven years in prison for her role in helping two convicted murderers escape from a maximum-security lockup is pleading for clemency in a handwritten letter obtained exclusively by NBC 4 New York. 

Joyce Mitchell was sentenced to 2 1/3 to seven years in prison in September after pleading guilty to charges related to providing hacksaw blades and other tools to Richard Matt and David Sweat, who broke out of the Clinton Correctional Facility last June. 

Remorseful and tearful at her sentencing, her letter to Acting Department of Corrections Chief Anthony Annucci echoed the statements she previously made in the courtroom. 

"Mr. Annucci, I realize what I did was very wrong. No one will ever know the remorse I feel for everything that happened due to my part in the Clinton Escape," Mitchell writes in the three-page letter from April. 

Matt was serving 25 years to life for the killing and dismembering of his former boss. Sweat was serving a sentence of life without parole for killing a sheriff's deputy in Broome County in 2002.

Officials said the convicts used tools to cut their way out of their adjacent cells and get into the catwalk between the cell block walls. They crawled through an underground steam pipe and reached a street near the prison walls through a manhole.

The pair eluded more than 1,000 searchers who combed the thick woods and bogs of northern New York for much of the next three weeks. Matt was killed by a border agent June 26. Sweat was wounded and captured by a state trooper two days later.

Mitchell admitted becoming close with the pair while she worked as an instructor in the prison tailor shop. She told investigators she agreed to be their getaway driver before backing out after suffering a panic attack at the last minute. The escapees were forced to scrub plans to head to Mexico and instead ran away after emerging from a manhole near the prison.

Police documents show that Mitchell performed sexual acts on one of the men, sent X-rated selfies to the other, provided tools to aid the prisoners' escape and knew the duo planned to kill her husband. 

In her letter, Mitchell describes Matt as a "powerful inmate" who had such sway over prison guards that they would leave open for him the cells of other inmates he didn't like. By the time they returned, she writes, "the inmate would have been beaten, they would just close the gate and walk away laughing and joking." 

Mitchell says she felt fearful that Matt would have her husband and family killed while he was on the run. 

"Please understand the person I was at the time was someone very scared for their family," she writes. 

Mitchell repeatedly speaks of her "remorse" and "regret," saying "I cry every day when I think of everything that everyone that was involved in the search and the community went through. I cry for all the pain my family is going through." 

At the same time, she adds, "I did go to the police station several days on my own to try and help, I turned myself in, and like I said above I tried to help with any information I could to try and bring these men back to prison." 

And Mitchell appears indignant when she takes issue with being publicly associated with prison breaks: "This will never go away, every time I turn around someone is saying they saw my face on TV with all these other prison breaks. I am in here, please tell why my face is being put up with something I had nothing to do with." 

Ultimately, she concludes, "I take complete responsibility for the wrong I did. I just hope you can help me."

Only the governor has power to grant clemency to prisoners in New York state. But the head of Department of Corrections can make recommendations to the governor. 

Mitchell's description of poor prison oversight at the Clinton Correction Facility matches the inspector general's findings, released in a report Monday.

Inspector General Catherine Leahy Scott found "that longstanding, systemic failures in management and oversight by DOCCS enabled two convicted murderers to meticulously orchestrate their escape from a maximum security facility almost in plain sight."

The report found that there should have been more than 400 prison checks in the months leading to the escape, any of which, if done properly, should have foiled the convicts' plans. One inspection failed to find the 18-by-14 inch hole cut in Matt's cell wall, the investigation found. 

The inspector general recommended strict compliance and monitoring of security procedures and expanded use of security cameras, restructuring the prison system's internal affairs division, and creating a general inspector general audit team to monitor security procedures at all state prisons. 

New York corrections authorities say they have made several security upgrades at the prison in northern New York where two killers escaped a year ago.

The Department of Corrections and Community Supervision says it will implement reforms throughout the prison system, and new cameras and security gates have been installed at Clinton Correctional Facility at Dannemora, 25 miles south of the Canadian border.

Spokesman Thomas Mailey says the prison also has retrained staff, disciplined employees responsible and named a new superintendent and senior administrators.

The union representing 18,000 corrections officers at New York's 54 prisons says this "disturbing incident" shined a light on the need for sustained investment in training, technology and tools.