A man is accused of fatally shooting a Castle Rock Township, Minnesota, woman on Christmas Eve, which, according to court documents filed Monday, was her birthday.

The criminal complaint said Dakota County Sheriff's Office deputies responded to the shooting at a Castle Rock Township home around 2:23 p.m. They found the man on the second floor of the residence with blood on his hands and the back of his head and the 26-year-old woman lying on the bed in her bedroom. She died at the scene. 

According to court documents, the man told the deputies the gun was in "the room" before he was taken to the hospital. Investigators found a handgun and two spent shell casings in the home. One of the casings was near the bed where the woman was found, and the other was underneath her. 

The woman's mother told deputies the man and woman lived in a room on the second floor of the home, and they had "two children in common," court documents said. The woman's brother, who also lives in the residence, said they had been together for between six and seven years but weren't married. 

According to the complaint, the woman's mother said one of the children ran downstairs and said they were scared after hearing something. They then asked the child what they heard, and the child "banged on the wall twice."

The woman's mother went upstairs and saw the man, who told them, "I've been shot. She shot me, call 911," per court documents, and then said, "I shot her."

The complaint said the mother then went into her daughter's bedroom and found her covered in blood on her bed "with her hands in front of her face as if she was protecting herself."

Court documents said the woman's brother was downstairs in his room when the woman's mother ran in to ask for help. He went upstairs and saw the man in the hallway.

Deputies later learned that the man told the woman's brother he shot himself and that "he caught the woman cheating," according to the complaint. 

The man is charged with one count of second-degree intentional murder, court documents said. If convicted, he faces up to 40 years in prison.

If you or someone you know needs help, you can contact the National Domestic Violence Helpline at 1-800-799-SAFE or Minnesota Day One at 1-866-223-1111.