Andre Gordon Jr., 26, gunned down his stepmother, his 13-year-old sister and the mother of his two children in separate locations in Falls Township, PA, after carjacking an elderly woman in Trenton to get there, authorities said.
The homeless gunman also bludgeoned his girlfriend's mother with the murder weapon, an AR-15 rifle, they said.
Platkin said Gordon then carjacked his way back to Trenton, where he was caught after citizens reportedly spotted him trying to inconspicuously flee one of the crime scenes.
Gordon is being held in the Mercer County Jail on charges out of New Jersey, the attorney general said. He'll soon be extradited to Pennsylvania to face a trio of murder counts, among multiple other offenses, he said.
"We will pursue justice for the victims and hold the defendant accountable for his reprehensible actions,” Platkin promised.
Gordon was wearing a black skull cap and what a 67-year-old woman who was with her 9-year-old grandson told police was a gas mask when he carjacked her in Trenton shortly after 8:30 a.m. Saturday, March 16.
SEE: Gunman Captured, Victims ID'd, Details Released In Hours-Long Trenton Hunt For PA Killer
An elite army of 60 or so local, county, state and federal law enforcers were searching for Gordon back in Trenton late Saturday afternoon when, witnesses said, a couple of local residents spotted him on the street and alerted city police.
He was soon in custody, nine hours after the nightmare began, Platkin said on Sunday.
"I am grateful to all the brave law enforcement officers who mobilized in the face of grave danger and helped ensure this incident ended without further harm," the attorney general added.
Members of the tactical team that converged on New Jersey's capital city boasted an array of expertise and experience.
They included officers from East Windsor, Ewing, Hamilton, Hightstown, Hopewell, Lawrence, Princeton, Robbinsville, West Windsor, the Mercer County Prosecutor’s Office, the Mercer County Sheriff’s Office, The College of New Jersey, New Jersey State Police, the FBI and the ATF, Platkin said.
His pursuers tracked the fugitive to a house where he was believed to have hostages. But he slipped out just before a SWAT team fired in tear gas and stormed the house.
A friend of the Gordon family and another person who were among the crowd of onlookers watching the SWAT operation reportedly spotted him near the corner of Brunswick and Phillips avenues shortly after 5 p.m.
They alerted a couple of city police officers.
Gordon surrendered to them, Trenton Police Director Steve Wilson said.
“My heartfelt sympathy goes out to the victims and their families,” Wilson said. “I'd like to thank the local, county, and state authorities for their immediate deployment of additional resources that helped prevent further injury and loss of life to the public and to any law enforcement officer."
“As law enforcement officers, we rely on our professional training and experience when handling events like this," NJ State Police Supt. Colonel Patrick J. Callahan said. "These situations are challenging and show the dangers law enforcement officers face daily."
J. Stephen Ferketic, director of the New Jersey Division of Criminal Justice, called the day's events "a profound tragedy and a shock that instilled fear in many residents in two states."
Gordon is charged in New Jersey with carjacking, multiple weapons possession counts, possession of large-capacity ammo magazines and hollow-point bullets, and possession of stolen property.
Meanwhile, Mercer County Prosecutor Angelo J. Onofri said members of his staff have been "in constant contact" with authorities in Bucks County, PA.
They "will work expeditiously," he said, "to ensure that Andre Gordon is returned to Pennsylvania to face his murder charges."
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