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DETROIT (FOX 2) - Police say that an Ypsilanti grandmother found in a shallow grave in her home's backyard was killed by her grandson.
Adding an extra layer of tragedy - and questions - is that the suspect's father believes his 29-year-old son was influenced by a cult beforehand.
"It's just a horrific situation," said Ronald Fleming. "The kid was pretty bright, but I guess he does have demons."
Fleming is still coming to grips with his mother Theadra's murder - and that police say his son, Ronald Savoy Fleming, was the killer.
"He was actually, I would call it radicalized, via a cult down in Tampa, Florida," he said. "We chased him down and found out."
Fleming believes it was the cult that allegedly led his son to kill his 73-year-old grandmother.
"What I found out is this is either the second or third situation in which after someone has been with this particular group, they came back and killed a member of their family," he said.
After he had not heard from his mother, her son requested police do a welfare check. But when police and Fleming made their way inside the home, they only found the 29-year-old suspect.
"I knew something was awry," he said.
After police questioned Fleming’s son, their investigation led them to the backyard.
"We were all out here looking, praying it can’t be this, but then when we looked - it was surreal," he said.
FOX 2: "Have you been able to talk to your son?"
"No," he said. "After having a detective explain to me the brutality of it, no, I can’t," he said.
Fleming says his mother was strangled to death. His son was arrested, and his arraignment was held this week.
On Friday investigators were back at the home as the investigation continues.
He says that now the family is focused on honoring the life of Theadra, a former nurse and expert quilter who he says loved her family and did everything she could for her grandson Ronald.
"Oh she’s going to be missed dearly," said Grace Fleming, the suspect's stepmother. "A tragic loss."
As the family continues searching for answers this father, has a warning for other parents.
"My experience (in) United States Marine anti-counter terrorism, it’s easy for someone to get radicalized," he said. "Because the person that he looked up to … wow."
The Ypsilanti home where Theadra Fleming was killed by her grandson, police say. Inset: Theadra Fleming