MINNEAPOLIS (WCCO) — Edward Muhammed Johnson’s first court appearance came Friday, just over two weeks since the brutal killing of Stillwater prison guard Joe Gomm.

The hearing was brief and to-the-point as Johnson uttered little. But afterwards prosecutors had plenty to say.

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Washington County Attorney Peter Orput says evidence gathered so far shows that Johnson acted alone; no other inmates appear implicated in the July 18 attack.

The 42-year-old Johnson arrived under tight security from Oak Park Heights, where he’s now being held. He was moved to the facility just a few miles away after the brutal hammer and knife attack that killed Gomm.

“I want to make sure especially the public that everyone knows that they are safe. Our courthouse is safe,” Washington County Sheriff Dan Starry said.

Prosecutors announced on Friday that they will call a grand jury within two weeks to consider indictments on first-degree murder, demanding the toughest charges under the law to both assure justice for the public and reassurance for badly shaken prison guards.

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Edward Muhammad Johnson in a 2003 mugshot (credit: MN DOC)

“While you are working to get more staff I’m working to keep you safe and the only tool I have is an aggressive prosecution,” Orput said.

When asked for a motive, Orput admits they may never know; Johnson isn’t saying. One possible theory is that Johnson’s attack came on the 14th anniversary of him losing an eye in a fight with another inmate. It is likely that he still harbored great anger over the incident. While Gomm was not involved in protecting Johnson at that time, a guard friend of Johnson’s was.

A prison door was left unlocked which may have allowed that attack.

“We haven’t been able to find a motive, we’ve got some ideas and we’re pursuing some possible theories. And while we’re not obligated to prove why someone did something, this may be one of those cases where we never know,” Orput said.

The 23-member grand jury will convene in the next two weeks to consider those greater charges.

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Despite now being held at the maximum security Oak Park Heights prison, Johnson’s unconditional bail was set at $1 million.