NEW YORK (Reuters) - Federal and New York state prosecutors will not pursue criminal charges in the death of a state prison inmate following an altercation with guards in 2015, officials announced on Wednesday.

FILE PHOTO: Samuel Harrell, an inmate at Fishkill Correctional Facility who died in April, is seen in a picture released by the New York State Department of Corrections and Community Supervision taken January 30, 2015. REUTERS/NY State Department of Corrections/Handout via Reuters

Acting U.S. Attorney Joon Kim and Dutchess County District Attorney William Grady concluded there was “insufficient evidence to meet the high burden of proof required for a federal criminal civil rights prosecution,” according to a statement from Kim’s office.

The death of inmate Samuel Harrell sparked protests and drew widespread media attention. His widow, Diane Harrell, sued New York state in state and federal courts.

She has said that Harrell died because he was handcuffed, punched, kicked and stomped by guards at the medium-security Fishkill Correctional Facility, including officers belonging to a group that inmates called the “Beat Up Squad.” The prison is about 70 miles north of New York City.

In a statement sent through their attorney, Luna Droubi, members of Harrell’s family said they were “deeply troubled” by the prosecutors’ decision.

“The decision of the U.S. Attorney’s office in no way alters the family’s continued demand for justice,” the statement said.

According to Diane Harrell’s federal lawsuit, the April 21, 2015, confrontation occurred after Harrell, who was diagnosed with bipolar disorder, announced he was going home despite having years left on his sentence for a drug conviction.

Harrell was pronounced dead at a local hospital. The county medical examiner ruled his death a homicide, describing the exact cause of death as an irregular heartbeat caused by high blood pressure after the altercation, according to Wednesday’s announcement.

Prosecutors said in the announcement that they did not have sufficient evidence to show that Harrell’s injuries resulted from intentional, reckless or criminally negligent acts by the guards, as would be required if they brought a criminal case.

Thomas Mailey, a spokesman for the New York Department of Corrections and Community Supervision, which oversees the prison, said that the department respected the prosecutors’ decision and declined to comment further.

A spokesman for the New York State Correctional Officers and Police Benevolent Association, a union that represents guards at the prison, could not immediately be reached for comment.