National Guardsman killed his daughters, 5 and 8, then shot himself in the head in custody battle murder-suicide after posting his eldest daughter's Christmas list on Facebook

A Tucson father who fatally shot his two young daughters before turning the gun on himself has died at a hospital, authorities revealed.

Pima County Sheriff's officials identified the man on Thursday as 37-year-old Levi Parker.

The father-of-two was pronounced in the afternoon from a self-inflicted gunshot wound. He had been on life support.

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Tragedy before Christmas: Levi Parker, 37 (left), has died from a self-inflicted gunshot wound to the head after authorities in Arizona said he killed his two daughters, Haylee Parker, 5, and Mackenzie Parker, 8

Crime scene: Deputies in Tuscon were called to Parker's condominium Wednesday evening after being contacted by the girls' mother reporting a threatening phone call from her estranged husband 

The young victim’s mother, Stacy Flowers Parker, called 911 shortly before 7pm Wednesday after receiving a threatening phone call from her estranged husband, whom she had been fighting for custody. 

Deputies responded to Parker's home in the 5700 block of North Kolb Road and spoke with him from outside the front door. They then heard a gunshot and forced entry into the house.

Inside, they came upon Parker and his daughters — 5-year-old Haylee Parker and 8-year-old Mackenzie Parker — all suffering from gunshot wounds.

The older girl was pronounced dead at the scene and the 5-year-old later died at Banner University Medical Center.

Levi Parker was taken to the same hospital with a gunshot wound to the head and was pronounced dead at around noon Thursday.

Stacy Flowers Parker (left) told law enforcement officials on Wednesday evening that her husband said that was the last time she would hear from her children (right) 

Holiday heartbreak: A month before the murder-suicide, Levi Parker shared on his Facebook page his daughter Mackenzie’s handwritten Christmas wish list (pictured)

Family man: The married father-of-two (center) worked as a manager at Raytheon, a major defense contractor, and served as sergeant first class in the Arizona Army National Guard

Dad: This image shows Parker in his US Army uniform cradling one of his daughter as a newborn 

Court documents indicate that Parker and his wife had been separated since September, and Pima County Sheriff Chris Nanos confirmed during a recent press conference that the couple were having legal problems, reported Tuscon News Now. 

Sheriff's Department spokeswoman Deputy Courtney Rodriguez said that on the night of the murder-suicide Wednesday, the girls’ mother told law enforcement officials that her husband said that was the last time she would hear from her children.

‘This is tough,’ Nanos said. ‘It's a couple hours before what's supposed to be the best day in the world for little kids... our community lost two little ones,’ reported the station KVOA.

Just one month before the domestic tragedy in Tucson, Levi Parker shared on his Facebook page his daughter Mackenzie’s handwritten Christmas wish list.

The 8-year-old was asking Santa Claus to bring her, among other things, a horse; a guitar; a hamster of gerbil; 'a paw print of rudolph'; some dark chocolates; a sewing machine and fabrics, and cooking supplies. 

Innocent girls: Mackenzie (left) was pronounced dead at the scene and Haylee (right) later died at Banner University Medical Center

The two girls (left and right) were staying with their dad this week because their parents had shared custody 

Happier times: The girls' mother and father had been separated since September and were locked in a custody battle. This image, posted by the victims' aunt, shows the couple years earlier  

Parker’s LinkedIn page shows that the married father-of-two worked as a manager at Raytheon, a major defense contractor manufacturing weapons and military electronics, and served as sergeant first class in the Arizona Army National Guard.

The children's relatives released a statement Thursday saying: ‘Please keep our family in your hearts and prayers in our unimaginable grief.’ 

Several local businesses and organizations, including two different funeral homes, have come forward offering their services to the girls’ family.