FORT PAYNE, Ala. >> An Alabama college student killed his mother during an argument over his bad grades, law enforcement officials said, and he was being held without bond in a county jail Monday.

Tyler Ryan Blansit, 22, confessed to killing Sherry Ann Blansit, 45, in Mentone — about 75 miles east of Huntsville, DeKalb County Sheriff Jimmy Harris said in a statement. Multiple news outlets have reported that she was found dead in her backyard Friday.

Blansit told investigators that he and his mother argued over his grades and that he struck the woman in her head, Harris said. The woman appears to have died of blunt-force trauma, he said.

“Usually we’ll have calls where a parent has whipped a child because of grades, a child has run away because of bad grades, but we’ve never had anything like this happen,” Harris told WAFF-TV. “It’s just one of those things you can’t explain; we’ll never be able to explain what went through his mind, why he snapped and did this.”

A University of Alabama-Birmingham directory said Blansit was studying biology. A university spokesman confirmed that Blansit was a student, but officials couldn’t comment further because of student privacy regulations.

Mentone police Chief Brad Gegg said the town’s population is roughly 400 and the slaying is the first to be reported in the community in years.

“I can’t find anybody that remembers there being a murder in the city,” Gregg said Monday. “It’s a small town, I think everybody knows everybody, and it was — I guess — kind of hard to swallow. But I think everything will be OK.”

Blansit is charged with murder and it’s unclear if he has an attorney. A call and emails to the county court clerk’s office weren’t returned.