Zakiiy Carson, 37, on Tuesday pleaded guilty but mentally ill to two counts of murder in the third degree, according to Lehigh County District Attorney Jim Martin.
Carson called 911 himself on Oct. 28, 2018, and told dispatchers he had shot his mother and sister, identified as Newark, NJ natives Latricia Ezell and Ashley Campfield, authorities said.
When officers took Carson into custody, he explained he had argued with his mom earlier that day about the treatment of his nephew, whom his mother cared for while the boy's mother was at work, Martin said.
A surveillance camera posted at the rear of a North 5th Street apartment building recorded the shootings, Martin said.
The recovered projectiles and casings from the scene were discharged from a semi-automatic pistol recovered from Carson's home, Martin said.
The Lehigh County coroner's office ruled that both women died of multiple gunshot wounds and their deaths were ruled homicides.
As part of the sentencing agreement, Carson will face 25 to 50 years in prison. He will also not be eligible for parole until he reaches age 60.
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