SOUTHGATE (WWJ/AP) – A man who was living with a woman and her son in a Downriver apartment has been charged in their deaths.

The bodies of 28-year-old Courtney Durr and 10-year-old Sumari Das were found late Sunday at La Colonnade Apartments in Southgate.

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An ex-convict, Antoine Beck, is accused of killing the pair and fleeing in Durr’s car.

The 33-year-old was arrested Monday and charged with first-degree murder, larceny and unlawful use of a car. He didn’t have an attorney on record as of Monday afternoon.

Police said the mother and son were found dead by family members around 10 p.m. Sunday inside their home near Northline and Dix roads near an elementary school.

Yellow crime scene tape enclosed the parking lot at the apartment complex as the victim’s mother, Barbara Durr, spoke to WWJ at the scene.

“She was a nice person, always helping people,” said Barbara Durr, of her daughter. “She was trying to help this guy get a job; was being friendly to him. She brought him by, he ate dinner, he came by on Mother’s Day, and now all the sudden you take my daughter and grandson’s life? While they sleep? I hope you rot in hell.”

Police confirmed that Beck spent 10 years in prison for armed robbery and had a relationship with Courtney Durr, which began a few months ago.

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Authorities said Beck had spend considerable with the victims in their apartment, and had been seen driving Durr’s car.

“…When they moved into the apartment — they’d been living in the apartment for a couple of months — he assisted them in moving in; so they’d at least dated from the time that they’d moved into the apartment,”  Public Safety Director Thomas Coombs said.

Coombs said the area is typically fairly quiet. “We have on an average one homicide a year, it’s what we have, occasionally there’s a second one. It’s a pretty quiet area.”

The investigation continues and authorities are waiting for autopsy reports — noting that the murders may have occurred on Friday and may have been committed using a Leatherman multi-tool.

“The officers and the medical personnel that responded to the scene indicating that they had been deceased for a period of time,” Coombs said.

Beck is due back in court for a hearing next week.

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