It’s a bizarre tale with a tragic ending and little explanation: A mentally unstable man began barging into strangers’ homes and, after assaulting an elderly woman, was shot and killed.

According to his family, Benjamin Beaudoin “struggled with a type of mental illness that was never positively identified but that involved severe migraines and their powerful side effects,” the Minneapolis Star Tribune reported.

Image source: Minneapolis Star Tribune

Police said Benjamin Beaudoin assaulted an elderly woman. (Image source: Minneapolis Star Tribune)

Beaudoin, 34, hailed from the Twin Cities, but was visiting the far northern community of Ray, Minnesota, for a wedding, his family said.

It remains unclear what triggered Beaudoin’s violent rampage, but it took two different armed men to stop him.

According to police, Beaudoin first broke into the home of Neil Reller around 5:20 a.m. Monday.

Reller snatched a shotgun and grappled with Beaudoin, hitting the intruder in the head so hard that the stock broke, the Star Tribune reported.

A bloody-faced Beaudoin then reportedly fled in his car, traveling 8 miles to the home of Ethel Himes.

He gained entry to the home by telling the 72-year-old woman that he had been assaulted, and when she let him inside, he began choking and beating her, police said.

Thankfully, she was not alone in the house.

“I’m the son who did what had to be done,” her son, Brad Himes, 48, told the newspaper.

The younger Himes came across his mother’s assault and rushed to his bedroom to grab his handgun, and when Beaudoin followed and attacked him, the son pulled the trigger, wounding Beaudoin fatally.

“We’re doing the best we can to get by,” Himes told the Star Tribune, saying his mother was not seriously injured. “Bad things happen. We just want to get over it.”

A friend of Beaudoin’s told the newspaper that he was shocked to hear of the invasions and assault, and that Beaudoin had, after struggling with alcohol early in life, spent the last 12 years sober.

The case is under investigation by the Minnesota Bureau of Criminal Apprehension and the St. Louis County medical examiner’s office, the Star Tribune reported.

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