A man died of a heart attack while he was burying a woman he strangled in his yard, police say

• A man died as he was burying a woman in his backyard, South Carolina officials said, per WJBF.
• Autopsy results show the woman died by strangulation and the man of a heart attack, police said.

A man died of a heart attack while he was burying the body of a woman he had strangled in his backyard, South Carolina officials believe.

Edgefield County Sheriff Jody Rowland and County Coroner David Burnett said in a joint statement on Tuesday that deputies were sent to a residence on Tanglewood Drive in Trenton, South Carolina, on May 7 after reports of "an unresponsive male lying in his yard."

The statement was first published by WJBF.

Upon their arrival, the officials found the body of Joseph McKinnon, 60, who appeared to have died of natural causes, the statement said.

The deputies also found another body close by that was wrapped in a plastic bag and lying in a freshly dug pit, per the statement.

That body was identified as Patricia Dent, 65, who lived with McKinnon in the residence, authorities said. The relationship between McKinnon and Dent is unknown.

Autopsy results released on Monday found that McKinnon died of a cardiac arrest while Dent died by strangulation, the statement said.

"Evidence gathered at the scene, along with statements from witnesses aided investigators to build a timeline, leading us to believe that Mr. McKinnon attacked Ms. Dent while inside their home," the county sheriff and coroner's statement said, per WJBF.

"Mr. McKinnon then bound her and wrapped her in trash bags before putting her in the previously dug pit. The pit was then partially filled in by Mr. McKinnon. While covering the pit, Mr. McKinnon had the cardiac event, causing his death."

The Edgefield County Sheriff's office did not immediately respond to Insider's request for comment.