Airway Heights, Washington - A Spokane County inmate has been sentenced to 25 years in prison for killing his 70-year-old cellmate, after learning that he raped his sister.

It was June 2020 when Shane Goldsby struck Robert Munger in the head more than 10 times before stomping and kicking him at Airway Heights Correctional Center, according to KHQ.

He was then subdued by correctional officers and has since pleaded guilty to second-degree murder after Munger died three days later from a fractured skull.

The 26-year-old said that while he never intended on killing Munger, he lost control as the man wouldn't stop tormenting him about his sister's rape.

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"He kept ... giving me details about what happened and what he did," Goldsby told the news outlet. "About the photos and videos of him doing this stuff, and it was building up."

According to Fox2Now, Goldsby's lawyer apologized to the dead man's family on his client's behalf during the sentencing hearing last week.

He added that he was ashamed of his actions: "I was put into a situation that I don't wish on nobody. I got a lot of fixing to do."

Goldsby said that he started panicking the second he learned that his cellmate was the man responsible for his sister's sexual assault years ago.

"I was in shock," he continued. "I was like, 'What the f***?' ... You're talking the same institution, the same unit, the same pod in the same cell as this dude. That's like hitting the jackpot in the casino seven times."

Goldsby stated that he complained at least twice to Airway Heights jail officials about the worsening situation, but nothing was done.

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"This shouldn't have happened, at all," he continued. "You're talking about this dude, who did some sick twisted things to my little sis. My family. My blood. My life. And you want to put me face-to-face with this dude?"

Prison officials declined to comment on how the two men ended up in the same cell together.

Robert Munger was serving a 43-year sentence for child rape, child molestation, and possession of child pornography at the time of his death.