DENVER (AP) – One of Colorado’s most infamous prisoners, theater shooter James Holmes, has been transferred to another prison, but officials won’t tell the public or the families of the people he killed where or why.

The move – which might have sent Holmes out of state or to a federal prison – was part of an exchange agreement with another prison, Colorado Department of Corrections spokeswoman Adrienne Jacobson said Wednesday.

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Such exchanges can happen for a variety of reasons, and revealing Holmes’ new location would “thwart the purpose,” she said.

The secrecy, which even extends to the prosecutors who spent more than four months trying his case, shows the extent of measures prison officials will take to control access at a time when a mass killer’s notoriety can make him a target for violence, and in Holmes’ case, create a following of supporters who send him fan mail and seek visits.

A search of online inmate databases in all 50 states and the federal Bureau of Prisons website failed to locate Holmes, but officials have the discretion to hide inmate names and locations from the public.

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The lack of information frustrated some victims who survived the shooting and District Attorney George Brauchler, the lead prosecutor in the case. Corrections officials sent victims, who are scattered across the country, a notification that Holmes had been moved but provided few other details.

“The system is set up to be so secretive on the back end, where the only focus seems to be the preservation of this guy’s life above and beyond any concerns of the community and the victims,” Brauchler said. “Is this a guy who is going to be potentially incarcerated in one of their states, and is it possible he could escape into one of the states where a victim lives? That’s a concern.”

It is at least the third time in five months that prison officials have moved Holmes, who was sentenced in August to life without parole for killing 12 people and injuring 70 others when he opened fire in a crowded suburban Denver movie theater in 2012.

He had been held most recently in San Carlos Correctional Facility in Pueblo after being transferred from the Colorado State Penitentiary in Canon City, the state’s highest security prison, where Holmes had his own cell and was heavily supervised.

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Several victims testified during Holmes’ sentencing that they didn’t want him imprisoned in California, closer to his parents who live near San Diego.

Deputy District Attorney Lisa Teesch-Maguire told victims in an email that prison officials assured her last year they wouldn’t move him to California, but they wouldn’t elaborate. She said the latest move was likely done for his security.

“He has likely been transferred to another state under a pseudonym,” she wrote. “And the Department of Corrections will not tell us what state he was moved to for the safety of the other inmates and other correctional officers in that state.”

Lisa J. Damiani, a lawyer who represented Holmes’ parents, declined to comment.

Prisons officials also would not provide any details about what inmates Colorado agreed to house in return for Holmes or any potential costs to Colorado taxpayers.

Colorado has transferred other high-profile inmates without disclosing their locations, including Austin Sigg, who was 17 when he was sentenced to life in prison for killing a 10-year-old girl abducted on her way to school.

Holmes “is perhaps the most notorious killer in the history of our state, certainly within memory. What did it take to get another state to agree to take him as a prisoner?” Brauchler said. “I’d like to know, why?”

– By Sadie Gurman, AP Writer

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