Wife accused husband of affair online before he allegedly killed her and their six children

Police in Michigan have identified a man accused of murdering his wife and six children last Friday before taking his own life.

Authorities have told the public that the mass murder fits the definition of 'family annihilation', one of eight reported across the US this year,

According to autopsy reports seen by The Guardian, Ottawa County Sheriff's Department confirmed that the Karolkiewicz family, including their six children, were all killed by gunshot wounds.

Kristopher Karolkiewicz is believed to have shot his wife, Amanda and their six children, before taking his own life. The family's home in Grand Haven Township was also on fire.

The report says that the fire at the home appeared to have been deliberately started by Kristopher, who had 'intentionally' set the blaze at numerous points across their property.

They added that they had not yet discovered the inferno's point of origin.

The Karolkiewicz family was found burning at their home following the 'family annihilation' (Mandy Karolkiewicz/TikTok)

Karolkiewicz, 47, worked for the American Heart Foundation as vice-president of sales and marketing, before losing his job in July this year. Amanda was an elementary school teacher.

According to Reddit posts reported by Detroit News, their marriage was on the rocks after Kristopher engaged in an 'emotional affair'.

The posts reveal that she was considering leaving him, but they were committed to working it out for their children.

"This is an unspeakable tragedy that we may never completely understand"

Ottawa County Sheriff Eric DeBoer wrote in a statement that was read out by Jacob Sparks, who is deputy captain: “This is an unspeakable tragedy that we may never completely understand.

“The investigation at this point shows that this was a murder-suicide, with the fire being started after the murders,” he added. “The case remains open and under investigation to try to get to the bottom and get answers of what happened leading up to the incident.”

Ottowa authorities say Kristopher Karolkiewicz shot Amanda 'Mandy' Karolkiewicz, 39, and their six children before dying by suicide. (Mandy Karolkiewicz/TikTok)

Emergency services were initially called to the Karolkiewicz property after reports of a 'smoky smell' near the home, but initially didn't find anything.

They returned about three hours later, to find smoke billowing from the property. After entering, they found the family's bodies, alongside their dogs and at least one cat.

Amanda's mother and stepmother Becky and Steve Lawwill described her as 'a kind and devoted soul who loved her family and her students' in a statement given to NBC News.

They added: "We treasured every moment we had with her and her six children, and words cannot adequately address our devastation."

A Facebook post from Grand Haven Area Public Schools from January spotlighted Amanda's work as a teacher. It read: "Mandy goes above and beyond for students, especially when they’re having a hard day, responding with empathy, patience, and care. She pours her heart into her work, is always willing to help wherever needed, and helps make Peach Plains a better place to learn and work."

The family's deaths appear to mark the 13th mass murder in the US in 2026, according to the Gun Violence Archive.

Eight of those officially fit the definition of a 'family annihilation', which is a crime usually committed by a male on 'multiple' family members.