A South Carolina man died of a heart attack after allegedly strangling his girlfriend to death.

According to reports, police found the body of Joseph McKinnon in the small town of Trenton, South Carolina, on Saturday after neighbors reported an unconscious man laying in his yard. EMTs were called to the scene but were unable to revive the 60-year-old.

Shortly after finding Joseph’s body, investigators learned the gruesome reason why he was in the backyard in the first place: the man was burying a body wrapped in bin bags in a newly dug hole. Officials identified the body as Joseph’s partner, Patricia Dent, who lived at the same home on Tanglewood Drive, according to a statement from Edgefield County Sheriff’s Office.

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The Edgefield County Sheriff said a post-mortem found that Joseph strangled the 65-year-old inside the home, and that neighbors recalled seeing him digging a hole in the yard the day before.

Authorities said McKinnon then bound Dent and wrapped her in trash bags before putting her in the pit. It appeared he’d nearly finished filling in the grave when he put down his spade, walked away, and collapsed from the cardiac event that caused his death.

Needless to say, the pair’s neighbors are shocked by the killing. Dawn Howanietz, who has been living a block up from where the bodies were found with her family for two years, told local station WJBF that she didn’t know there was a danger to neighbors after the grim discovery was made.

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She lamented:

“We have no idea and that’s what we’re asking about at least let us know that it’s something they have in control or don’t have in control do we have to make sure everything is locked up tight watch our dogs or our animals we got a farmer back there too you know it’s scary.”

Meanwhile, Patricia’s twin sister, Pamela Briggs, told Fox Carolina:

“I would say a nightmare, and I want to wake up, and it’s a dream. I know it’s not. This is reality and life, and a big part of me is gone, and now I’m going to have to live with that.”

Our hearts go out to the victim’s loved ones.

[Image via WJBF]