Police continue to look for a possible motive in the shooting death of Gretchen Crooks, allegedly by her 13-year-old son Noah.
Police responding to the Crooks home, in Osage, Iowa, on Saturday night, found the woman shot multiple times after her teenage son - the alleged shooter - called 911.
'We're at a loss. These are good people,' sheriff Curt Younker said.
Killer: Noah Crooks, left, allegedly shot his mother Gretchen, right, multiple times in her Iowa home and then called police
There was no history of domestic abuse or criminal records associated with any Crooks family members.
The 13-year-old boy who allegedly shot his 37-year-old mother dead with a hunting rifle is also facing 'unheard of' charges that he tried to sexually abuse her.
Now, authorities are saying Noah Crooks also tried to sexually abuse his mother, which mental health professionals say they have never encountered among juveniles.
Charges filed today in Mitchell County District Court further accuse Noah Crooks, an eighth-grader at Osage Middle School, of assault with attempt to commit sexual abuse against his mother.
Shelia Aukes, a licensed social worker in Des Moines who works with young people on a variety of mental health issues told the DesMoines Register: 'The victims in most sex offenses committed by juveniles are siblings, other juveniles or, more rare, other adults.
'A child or adolescent sexually abusing a parent is completely out of the norm, totally unheard of.'
Weapon: A motive for the shooting has yet to be reported while the victim's husband, pictured, had a penchant for guns according to his Facebook page
Crooks is believed to have fired a .22 calibre at his mother on Saturday at their rural home and four days later a motive has yet to be established.The teen was said to be calm and emotionless when he called 911 reporting the shooting.
'The emotions of the young man, from what I've been told, is his demeanour was very calm and kind of stoic. Almost like he was in shock also,' Deputy Greg Beaver told KTTC.
He is currently being held at the North Iowa Juvenile Detention Center in Waterloo and charges are expected to be filed today. He will be tried as a juvenile.
Iowa law allows children ages 14 and older to face crimes in adult court.
Mitchell County Sheriff Curt Younker told the DesMoines Register: 'We’re at a loss. These are good people, very responsible. It is the most heartbreaking thing I’ve ever seen.'
Home: Police reported the teenager as sounding calm on the phone though perhaps in shock by what had just happened
'We have lost our daughter. We have lost our grandson,' Mrs Crooks' mother Beverly Brahm of Mason City told the Albert Lea Tribune.
Mrs Crooks, who was listed with her husband William Crooks as the rural Osage property owners, had worked as a nurse at Mercy Medical Center-North Iowa while also studying toward her master's degree after accepted at the University of Iowa in 2009.
On her Facebook page back in 2010, she praised her son, one of two sons according to Mrs Brahm, for his musical talents on the saxophone as well as his accomplishment in being accepted into a University of Iowa camp to learn Chinese.
'So proud of him!' she wrote.
She had also recently published an application on her page reading: 'Click "like" if you love your son!'
Praise: The mother had praised her son on her Facebook page for his acceptance into a Chinese language camp at the University of Iowa as well as his playing of the saxophone
Arrest: The 13-year-old was taken into custody without incident and taken to the North Iowa Juvenile Detention Center where charges have not yet been filed
The Mitchell County Sheriff's Office says their investigation is ongoing with few further details in the killing reported such as where the weapon came from.
William Crooks' Facebook page shows his interest in the US Concealed Carry association as well as the Springfield Armory, a company that sells pistols and rifles.
The State Medical Examiner’s Office as well as the Iowa Division of Criminal Investigation are continuing their investigation as well.
Her family expressed their great sadness by her death while her 35-year-old brother Jason thanked friends and family for their support.
'I just want to extend my gratitude to family and friends for their support during this time,' he told the WCF Courier.
Her co-workers at Mercy Medical also released a statement obtained by the Courier, reading:
Nurse: Mrs Crooks worked as a nurse at Mercy Medical Center-North Iowa while also studying toward her master's degree at the University of Iowa
Grade school: The boy's school of Osage Middle School says they're contacting students' families and offering counseling
Serving as a critical care nurse, she cared for patients in a makeshift hospital.
Her son, an eighth grader at Osage Middle School, the boy's school's superintendent told ABC 6 that they have since begun reaching out to the other students' homes while also offering counseling.
'It's gut-wrenching, you know?' Osage Superintendent Steve Bass told ABC. 'It's always tough in a small community when anyone dies for any reason but then you hear that a student is involved in any shape or form, it kind of goes to another level.'
