Frazier Glenn Cross, Jr., also known as F. Glenn Miller, appears at his arraignment on capital murder and first-degree murder charges at the Fred Allenbrand Criminal Justice Complex Adult Detention Center on April 15, 2014 in New Century, Kansas. (David Eulitt-Pool/Getty Images)

Frazier Glenn Miller, the 72-year-old suspect in this month’s Kansas City shootings, in which three people were killed, was a well-known anti-Semite and former Ku Klux Klan leader with a long, public history of hate. He was also, ABC News reports today, an FBI informant who struck a deal with authorities in the late 1980s in which he gave up information about fellow white nationalists for a reduced prison sentence, along with protection and a new name upon his release in 1990.

On April 30, 1987, Miller—who was wanted by U.S. Marshals after disappearing while appealing a conviction for criminal contempt—was discovered in a trailer with “hand grenades, automatic rifles, pistols and flak jackets,” and forced out by authorities. Facing a sentence of 20 years, he agreed to a plea deal with the FBI.

ABC News reports:

Eventually, McCullough, the federal prosecutor, would approve a plea deal with Miller recommending a five-year prison sentence in exchange for his cooperation and testimony against his former compatriots. He would serve less than three years of that sentence at a prison in western New York.

“I am not certain that we got 100 percent of what we wanted,” McCullough told WTVD. “He did testify in a couple of cases here in the eastern part of the state, or agreed to testify where the people plead guilty knowing he was going to testify.”

Miller was given the name Frazier Glenn Cross in 1990 upon his release from prison, and the FBI granted him protection from both his original targets and his former compatriots, sending him to Iowa and then Nebraska.

“He asked for protection from both the White Patriot Party people and blacks in prison because he had alienated both groups,” says McCullough. “Obviously once he served his sentence he couldn’t go back to where his old compatriots were because he would be at risk. So we had to put him somewhere safe.”

Miller currently faces charges of capital murder and first-degree murder for the deaths of William Lewis Corporon, Reat Griffin Underwood, and Terri LaManno.

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