Daughter's heartbreaking last words to mum 'abducted and trapped in car boot' before her death.

In the minutes before her death, an allegedly abducted Montana woman made a frantic phone call to her loved ones.

Rita Maze, 47, told her husband and daughter she was trapped inside the boot of her car, whispering down the line that she had been attacked by “a large man in a black hoodie”.

“I told her that I loved her,” her daughter Rochelle told the Great Falls Tribune.

“That’s the last thing she ever heard.”

The conversation lasted just 10 minutes before the phone went dead.

“She travelled with a gun, and she knew he had her gun, and she was terrified,” Rochelle said.

“He kept her in the trunk for 12 hours.”

The family contacted local police who used the phone to track Rita, but were too late to save her.

Her body was found inside her vehicle on Wednesday, near Spokane International Airport.

The coroner has since revealed she died from a single gunshot wound to the chest and abdomen but stopped short of labelling her death a homicide.

Before her death, the mother-of-two described how she was hit over the head and kidnapped at a rest stop some 500km away after visiting relatives.

However, police say they have not ruled out the possibility her injury may have been self-inflicted, according to KHQ.

The Spokane Sheriff also confirmed there is no person of interest in the case and said authorities were looking at a surveillance video from a nearby convenience store.

Detectives said Rita’s body was found in the car boot with her keys were still in the ignition, a purse on the front seat and a $20 note close by. There was also blood outside the car.

They are now trying to piece together what happened.

But her family refuse to believe she took her own life, with Rochelle stressing her belief her mother was abducted.

"She did not hit herself, stuff herself in the truck and drive all the way to Spokane and shoot herself," the daughter said, according to The Spokesman Review.

“I believe they shot her and left the gun and keys in there to make it look like she killed herself.”

"My mom touched every person she made contact with," Rochelle said of her mother, who spent years working as a teaching aide and cook in several schools.

"She loved her grand kids so much."

Maze had two granddaughters, Addyson, 4, and Carly, 1, belonging to her son, Michael.

"Growing up, my mom was an amazing mom," Rochelle said.

"She was fun loving and had an infectious smile and was goofy and a child at heart," she said. "And she had fun all the time."

Anybody experiencing mental health issues is urged to call Lifeline on 13 11 14 or BeyondBlue 1300 224 636