MINNEAPOLIS - On a day when President Barack Obama called ISIS one of the most dangerous terrorist groups this country has dealt with, NBC News has learned that a Minnesota man died while fighting for them.

Douglas McArthur McCain, 33, went to school at Robbinsdale Cooper High School in New Hope. He attended classes in the district from 1997 through 2000. This week his family was notified he had been killed in a clash between ISIS and the Free Syrian Army.

KARE 11 sat down with McCain's cousin, Kenyata McCain, at her north Minneapolis home Tuesday night. The young woman fought for words and repeatedly said "he was not a terrorist."

Kenyata said she'd just communicated with her cousin Douglas on Facebook last week and described the notion that he was an American Jihadist killed fighting for ISIS as ludicrous.

"We're from Chicago. We grew up in Minnesota, he's not a terrorist! That's crazy" she said.

McCain called himself "Duale ThaslaveofAllah" on Facebook and his family says he converted from Christianity to Islam around 2004.

"His religion was very important to him, but those people -- the ISIS people -- they don't represent what my cousin's beliefs are or were at all," said Kenyata.

On social media, he reportedly posted a number of pro ISIS comments, posts his family are now looking at in a new light.

Beginning in 2000, McCain had a series of minor run-ins with local Minnesota law enforcement. He was arrested for disorderly conduct, theft, obstruction, driving without a license and a minor marijuana possession. He was arrested in 2008 for giving police false information.

The family was notified on Monday by the State Department that he'd been killed in a clash between ISIS and the Free Syrian Army. His cousin says all she can think about is the boy she grew up with.

"He used to always grab our cheeks ... that was his little signature thing that he did through our childhood. I think I'll remember that the most about him."

Several months ago McCain told his family he was travelling to Turkey. That was the last they saw him.