PHILADELPHIA -- The man facing murder charges in a mass shooting that left five people dead in a Philadelphia neighborhood Monday "obviously planned" the rampage, but the investigation of the killings could take months as authorities dig for more details, a district attorney said.
Kimbrady Carriker, 40, acted alone when he prowled a Philadelphia neighborhood in a bulletproof vest and ski mask, firing randomly at vehicles and pedestrians, authorities allege.
Investigators are now combing through Carriker's social media history and looking into the suspect's possible mental health issues, Philadelphia District Attorney Larry Krasner told CNN on Wednesday. Carriker is being held without bail and has not entered a plea. "I can certainly tell you that there are indications of mental health issues. There are indications of irrational behavior. There are indications of irrational statements and irrational acts," Krasner said.
The Philadelphia Public Defender's Office, which is representing Carriker, said Wednesday it would not comment on the case at that time.
New details emerged Wednesday about a possible motive for the shootings in Philadelphia's Kingsessing neighborhood. Five people, including a 15-year-old boy, were killed and several others were injured.
The suspect used so-called "ghost guns" in the attack, authorities allege. On Wednesday, the city of Philadelphia announced a lawsuit against two companies that supply parts for such weapons, which can be made from components purchased online.
Carriker allegedly told police he carried out the shooting to clean up the neighborhood, two law enforcement sources told CNN.
The suspect's social media activity has also come under scrutiny. A deleted social media page believed to be Carriker's featured a series of posts about guns, the Second Amendment and "loss of freedoms," according to a law enforcement source.
Hours before the Monday night shooting, a public post on the page showed a video advertisement for a tactical weapons accessories company. The video, posted at 10:49 a.m. ET, shows a man in tactical gear, holding what appears to be a military-style rifle.
First reports of the shooting came around 8:30 p.m. Monday, authorities said. Officers eventually arrested Carriker in an alley after a chase on foot. He had an AR-style rifle, a 9 mm handgun and a scanner that tracks emergency response radio traffic, authorities said.
The attack was among at least 360 mass shootings in the US so far this year with four or more wounded, excluding shooters, according to the Gun Violence Archive. It unfolded amid other scenes of carnage this week in Fort Worth, Texas, Indianapolis and Baltimore.
Investigators in Philadelphia see "all kinds of indications of premeditation," both in how the weapons were purchased and the clothing worn during the shooting, said Krasner, who is leading the investigation. "But when you get into issues of psychological state, motivation, intent beyond the obvious, which is that he obviously planned this ... that can be a monthslong process," he told CNN.
That process includes going through cell phones, social media, using high-level technology and extensive interviews to try to learn more about the shooting, Krasner said.
Carriker was arraigned Wednesday on charges of murder, attempted murder, assault, reckless endangerment and weapons charges.
The gunman is suspected of killing Daujan Brown, 15; Lashyd Merritt, 20; Dymir Stanton, 29; Ralph Moralis, 59; and Joseph Wamah Jr., 31, police said. Wamah's body was found in a home early Tuesday, while the others were found Monday night, authorities said.
Philadelphia sues ghost gun suppliers
The AR-style rifle and 9 mm handgun found in Carriker's possession were privately made weapons known as ghost guns, according to Frank Vanore, deputy commissioner of investigations for Philadelphia police.
The firearms didn't have any markings and are not traceable, Vanore said.
The city of Philadelphia on Wednesday filed a lawsuit against two ghost gun suppliers, Polymer80, Inc. and JSD Supply, which it says are among the largest suppliers of untraceable firearms confiscated in the city.
The lawsuit alleges the companies "have perpetuated the gun violence crisis and threatened the public's right to health and safety by marketing, selling, and dispersing unserialized ghost gun kits into Philadelphia," the city said in a news release.
The suit "seeks to stop Polymer80 Inc. and JSD Supply from continuing their negligent and illegal business practices, in addition to the payment of damages," the release states.
CNN has reached out to Polymer80 Inc. and JSD Supply for comment.
Ghost gun confiscations in Philadelphia have increased 300% in the past three years, Philadelphia Mayor Jim Kenney said. Kits from which the guns are made are sold online without the buyer needing to pass a background check and without serial numbers on the parts, he said.
The city's police department says it confiscated 575 ghost guns while conducting criminal investigations in 2022. Eighty-seven percent of ghost guns recovered in criminal investigations this year were manufactured by Polymer80, the city said in a news release.
"This is like a level of insanity that no one should ever deal with," Kenney told CNN on Wednesday.
After a previous fatal shooting in Philadelphia, Kenney tried to enforce a ban on firearms in its recreation facilities, but a judge blocked it in October, citing a state law that prohibits local governments from regulating firearms possession.
Suspect's behavior prior to shooting under scrutiny
Prior to the shooting in Philadelphia, witnesses said Carriker had been acting oddly and displayed "abnormal behavior for quite a while," Philadelphia Assistant District Attorney Joanne Pescatore said during a news conference Wednesday.
People who lived in the same house as Carriker said "he was getting more and more agitated as the days were passing," Pescatore said.
Carriker had also handwritten a will, dated June 23, which investigators recovered while executing a search, Assistant District Attorney Bob Wainwright said. The will did not include any mention of plans to carry out the shooting, Wainwright said.
Investigators also found a .380-caliber handgun, ammunition and live rounds that matched ammunition found at the scene of the shooting, Wainwright added.
Meanwhile, the suspect's social media history revealed that he shared posts from pro-gun groups supporting former President Donald Trump and the Second Amendment.
Last month, he shared a mocking video of a speech by President Joe Biden and added his view that Biden was trying to "take our arms."
Another post from the same day says, "The only thing more terrifying than blindness is being the only one who can see."
The page also has references to God and prayer posted over the last week, including a passage from the book of Isaiah posted by Carriker that begins, "I alone am the Lord, the only one who can save you."
In one post, he complained about what he believed was a loss of freedom. And in a repost this week, he pinned a quote that read, "So often we accept the loss of freedoms in the name of safety. But we never feel any safer and we never get the freedoms back."
In a June 20 post, he said of crime in the community, "During community patrols I have notice a big shame. So many of our 50 + 60 + 70 year old elders are influencing the youth negatively. They are without a doubt promoting and participating in robbing, prostitution, scamming, and murder."
Another post on Carriker's Facebook page shows photos of armed protesters dressed as Black Panthers taken at a 2020 Atlanta protest. He also shared that they were "exercising their first and second amendment" rights.
Community is traumatized, mayor says
The Kingsessing neighborhood where the deadly mass shooting unfolded is traumatized, Kenney said.
"They're traumatized, and obviously, rightfully so. There's no reason in the world that that situation should have happened Monday night," Kenney told CNN's Jake Tapper. "And the common denominator in all of these things are guns, and the availability of guns and the high capacity of guns."
In addition to the five killed, two boys, ages 2 and 13, were each shot in the leg and were in stable condition, police said. A 33-year-old woman and another 2-year-old boy were injured by glass, authorities said.
The two 2-year-old children are twins who were in a car with their mother when shots were fired at them, authorities said.
Referring to the Second Amendment, the Democratic mayor said, the Founding Fathers "weren't talking about AR-15's to mow down people in the streets of Philadelphia."
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