He volunteered to deploy overseas with the Milwaukee-based 1st Battalion, 121st Field Artillery Regiment in 2006. The unit was tasked with protecting convoys moving from Kuwait into northern Iraq, Guthrie said.

He served as a vehicle gunner and was involved in a small-arms battle in Iraq in November 2006, she said. She did not know exactly where the battle took place. Magdzas received a combat action badge, an award that recognizes participation in combat. His deployment ended in 2007.

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Some time after returning to Wisconsin, Magdzas went to work as a firearms instructor for Better Defense, a shooting school that provides classes in northern Wisconsin and southern Minnesota. According to his profile on the school's website, Magdzas began shooting before he was 12 years old. It also said he received the Purple Heart, an award given to US military personnel wounded or killed in battle. Guthrie said there is no record he received the honor.

The school's chief executive officer and master instructor, Gary Bjergo, did not immediately respond to phone messages Thursday seeking comment.

Oles-Magdzas attended Carlton High School in Carlton, Minn. Her science teacher, Deb Saunders, described her as an artistic, "sparkly" young lady who was into dancing and cheer leading. She often stopped sad-looking students in the halls to ask them what was wrong, Saunders said.

Buscko said she worked with Oles-Magdzas, and briefly with Magdzas, at Community Connections, a Duluth foster care facility for people with brain injuries. Oles-Magdzas had recently left the home, however, to take a job as an assistant cheer-leading coach this fall at Duluth East High School.

"April's passion for working with young people was evident to everyone that came into contact with her," the school's activities director, Shawn Roed, said in a statement. "She will be sadly missed and our thoughts and prayers go out to her family and friends."

Investigators recovered a 9-millimeter handgun in the house they believe Magdzas used. They also discovered what appeared to be a bomb in a backpack in the house, but explosives experts later determined it likely wasn't and destroyed it.