An Oregon mother shot and killed a man after she found the stranger in one of her children’s bedrooms, authorities said.

The 33-year-old mother and her two children, aged 10 and 5, had come home at about 1:45 a.m. Sunday when she spotted the intruder hiding in her Portland home, according to reports.

Already armed with a handgun, the unidentified mom opened fire, fatally striking the 59-year-old man, WCVB reported.

The woman and her children were not harmed, but are in shock, Portland Police Sgt. Pete Simpson told the television news station.

Read: Brave Homeowner Tackles Intruder and Wrestles Gun From His Hands

Calling the incident a “very scary situation,” Simpson said: “She is understandably traumatized by what happened as [are] her children and we are going to help her with that side of things, as well.”

Police are working to determine why the man was in the home, which had previously stood vacant until the woman and her children moved in, a neighbor told KOIN 6 News.

“I know when the previous renters were there, there was a lot of mischief,” neighbor Amber Murray told KOIN 6 News. “After they moved out I think there were a few squatters in the home.”

Read: Boy, 7, and Parents Murdered By Intruder Who Was Shot Dead, Identified By Police As Neighbor

Charges have not been brought against the woman, who is cooperating with police in the investigation.

The case will be presented to the Multnomah County District Attorney's Office for review after the police investigation is complete.

The man’s identity is expected to be released after his family is notified of his death. His autopsy is scheduled for Monday.

Watch: Intruder Hides Under Children's Blanket While Robbing Home