'Creepy' former co-worker 'stalked' mum of four before death

A "creepy" former coworker has been arrested for allegedly murdering a mum of four whose friends claim he became obsessed with after he retired.

The body of Masako Yamada Kenley was found with a gunshot wound to the chest in thick bushland in Sandy, Utah, on the evening of July 4 (local time), police said.

She had been covered in "heavy layers of grass and foliage", a police affidavit said according to news outlet KSL.

The 53-year-old was last seen about 4pm on July 2 in the nearby town of Midvale.

Masako Yamada Kenley whose body was found on July 4.
The body of Masako Yamada Kenley was found with a gunshot wound to the chest in thick bushland. Source: 2KUTV

Her family said Ms Kenley left her home to meet friends for dinner, but never arrived, KSL reported.

One day after her body was found, police arrested 75-year-old William O'Reilly, who they said was Ms Kenley's acquaintance, for aggravated murder, desecration of a corpse and obstruction of justice.

The affidavit said O'Reilly was found by police at a hospital after trying to take his own life.

Officers claim they found Ms Kenley's GPS device for her car, her purse and one of her shoes inside the boot of the 75-year-old's vehicle.

Friend claims alleged killer 'stalked' mum

While a motive for the alleged murder has not been revealed by police, Ms Kenley's long-time friend, Tracy Collar, told 2KUTV the pair used to work with O'Reilly at the United States Postal Service.

Ms Collar, who Ms Kenley was supposed to be meeting for dinner when she disappeared, said O'Reilly "stalked" the 53-year-old.

"The weirdness came in after he officially retired from the post office, and he would drive from his house to Masako's house to deliver fresh eggs," Ms Collar said.

However, over time his attention increased and Ms Collar claims O'Reilly began following and threatening Ms Kenley.

Pictured is 75-year-old William O'Reilly who was Masako Yamada Kenley's acquaintance.
One day after her body was found, police arrested 75-year-old William O'Reilly, who they said was Ms Kenley's acquaintance. Source: 2KUTV

"I was there; I witnessed the whole thing. Lots of stuff happened and so it was very creepy. And very not normal," she said.

"I'm afraid that she stood up for herself, and he shot her and killed her because I think he was so deranged that he was under the assumption of, 'if I can't have her, nobody can'."

Ms Collar said she wasn’t concerned when Ms Kenley didn’t arrive for their meal and believed she’d been held up at work.

She described her friend as a "very happy-go-lucky" mum who lived for her children.

Devastated family releases statement

Ms Kenley's family has released a statement on a GoFundMe page created to help pay for funeral expenses.

"These past few days have been an absolute whirlwind of emotions," they said.

"It is amazing to see so many people that we know, and even many that we do not, supporting our family during such a difficult time in our lives.

A missing poster for Masako Yamada Kenley.
Her family said Ms Kenley left her home to meet friends for dinner, but never arrived. Source: 2KUTV

"We wish we could thank each of you, in person, who has donated and expressed their love. Thank you for everything you have done for us.

"These donations have already made a huge difference, allowing us to make preparation for the funeral, bringing family from Japan to the United States, and picking a location for our mother to be laid to rest."

Readers seeking support and information about suicide prevention can contact Beyond Blue on 1300 22 4636, Lifeline on 13 11 14 or Suicide Call Back Service on 1300 659 467.

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