This Friday, Sept. 15, 2017 photo shows the Whiting Forensic Division maximum-security psychiatric hospital in Middletown, Conn. Allegations of staff misconduct at Connecticut's only maximum-security psychiatric hospital are mounting after a whistleblower complaint about abuse of a patient led to some staff suspensions and several arrests. (Photo: AP/Dave Collins)

Letters written by the patient at the center of an abuse investigation at Whiting Forensic Division show the alleged abuse may have gone on for more than a decade.

A staff member gave the letters to the NBC Connecticut Troubleshooters, letters in which the patient wrote to doctors and others at Whiting Forensic complaining of abuse. People close to the patient confirm the letters are in his handwriting and one of those letters dates back to 2006.

The state's investigation of alleged abuse at Whiting, Connecticut's maximum security mental hospital, began after a surveillance video from the patient's room was brought to the attention of management in early 2017.

The letters given to the NBC Connecticut Troubleshooters show the patient had complained about his treatment more than a decade earlier than that.

In a letter dated May 19, 2008, the patient wrote that a staff member "is trying to kill me."

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