BUFORD, Ga. -- Police in Gwinnett are working to find out what led a man to strangle a mother and her 2-year-old son.

Thirty two-year-old Brandon Williams of Buford is charged with one count of felony murder and two counts of aggravated assault in the attack that happened late Sunday night in Buford, Ga.

Officers responded to a home on the 2700 block of Tybee Drive around 11 p.m. Sunday after receiving a call from the homeowner. The caller reported that the suspect, his son, choked his girlfriend and her toddler who lived at the house, then walked up the street to a gas station. Police found Williams at a RaceTrac gas station where he was arrested.

Both victims were taken to the hospital where they died.

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The boyfriend, who did not want to speak on camera, told 11Alive he is devastated and hates his son for what he did.

Loved ones who knew the mother and son made their way to the crime scene Monday morning. Brent Lenz said he's been friends with the mother since 7th grade. He identified her as 30-year-old Natalie Nation. Her 2-year-old's son is Cole Nation.

The homeowner said he was working on a car in the driveway when the incident happened. He said he noticed his was son acting strange and wearing a mask before the attack. Police have not confirmed if Williams wearing the mask during the attack.

Police said the woman rented a room inside the home and detectives confirmed there were no family ties between the suspect and the victims.

Williams is being held at the Gwinnett County Detention Center where he will remain without bond.

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