MINNEAPOLIS (WCCO) — We are getting a first look inside the investigation of a deadly attack on a corrections officer.

An inmate murdered 45-year-old Joseph Gomm at the Stillwater prison in 2018. WCCO investigates what the never-before-seen evidence reveals and the warning the killer had sent in the mail.

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“I was doing the rounds, and then I heard a staff assault call,” one corrections officer said as he recounted that day to investigators from the BCA. “The door was closed, barricaded, and all I could hear was, ‘He has a hammer! He has a hammer!'”

“He was bleeding everywhere and I seen him struggle for life,” another corrections officer said.

The deadly attack on a corrections officer on the floor of a metal shop sent panic through Minnesota prisons and state investigators on a search for answers.

For the first time, we are seeing Edward Johnson in handcuffs sent to segregation one hour after the attack. Along with pictures of his cell littered with scribblings of a conspiracy, corruption and lies. Thoughts he did not keep to himself.

“I heard it was that one guy with one eye,” one inmate said of Edward Johnson. “He’s a little crazy.”

Joseph Gomm (credit: CBS)

“Hell yeah, he’s crazy in the head,” another said.

In a rambling letter to relatives, Johnson wrote, “You will all hear some very bad news real soon.” Sixteen days later, Officer Gomm was dead. As he unlocked an area in the shop, Johnson got ahold of a small sledgehammer from the wall of tools. WCCO has also learned he used two homemade weapons hidden in the shop to stab Gomm before hitting him in the head with that hammer.

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Nearly three years later, it seems clear Johnson shouldn’t have been allowed near such dangerous objects at all. He’d already racked up a five-page discipline report and was ordered to spend nearly 5,000 days in segregation. He served fewer than half.

Fourteen years to the day before he killed Gomm, Johnson lost an eye when an inmate stabbed him. It’s believed a corrections officer became his target to mark that anniversary.

Gomm’s sister, Audrey Cone, is calling on Gov. Tim Walz, who’s supported her family in the past, to push legislators to approve a $3 million settlement to avoid reliving the gory details in court.

“[Walz] said we as a state failed Joe, and nothing they would say or do would bring Joe back,” Cone said. “The evidence is just very disturbing … Some days we get emotional. For us it’s just part of the grieving process that we haven’t been allowed to have.”

The Minnesota Department of Corrections sent WCCO the following statement when we asked about the evidence in this case:

Since the death of Officer Joe Gomm, substantial changes have occurred at Stillwater. Changes include a comprehensive look facility-wide at operations, eliminating double-bunking, improving staffing patterns and levels in industry areas, revision and updating of the tool control policy, improving work area layouts, along with updates and additions to camera systems. Staff no longer work alone with the incarcerated population. When an individual staff members passes through an area, staff have visuals of each other or are monitored on camera. Security personnel in the industry shops do rounds on a two-person basis.

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The DOC also told us no metal workshops are currently open.

Liz Collin