UPDATED 09/12/11 5:30 p.m.
PALOS PARK, Ill. (CBS) -- Police are questioning a person of interest after a husband and wife were found dead in their home in unincorporated Palos Park over the weekend.
John Granat, 44, and Maria Granat, 42, were pronounced dead Sunday morning at their 81st Court residence, according to the Cook County Medical Examiner's office. Autopsies on Monday found John Granat died from multiple blunt force injuries from an assault, while Maria Granat died from multiple blunt and sharp-force injuries. Both were ruled homicides, the medical examiner's office said.
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Cook County sheriff's police are holding a person of interest in custody, who was being questioned as of 11 a.m.
Sheriff's police received a 911 call at 7:12 a.m. from someone in the family's home. The caller said the two residents were dead, according to a news release.
The caller, a male relative, was in the home when police arrived and was being questioned by authorities, a source said.
Neighbor Dimitri Hatzelis says the couple had a son who appeared to be in his late teens who lived with them. The sheriff's department won't say if that son is the person who called 911 on Sunday.
"I remember him just taking the bus from school and coming home, just walking down the street by himself," Hatzelis said of the son.
The husband and wife suffered blunt force trauma, and had injuries to their torsos, hands and faces, a source said.
Police spent all day Sunday interviewing people who knew the couple and collecting evidence around the house.
Neighbors said the family had lived in the home for a while, and that John Granat was a local contractor and owned a family home improvement and landscaping business in the area.
"It's very aggravating, especially in this town," said neighbor Bill Robinson. "I grew up in this town, a couple blocks away, and as far as I know, this may be the first time there's ever been a murder in Palos Park. We're lucky if we have a robbery – it's been that quiet of a town; a very quiet town, so it's a real shocker, actually."
The Sun-Times Media Wire contributed to this report.
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