PITTSBURGH (KDKA) -- Police spent the night searching for a suspect after multiple people were shot at the Monroeville Mall Saturday night.
Police were called to the scene around 7:30 p.m. after receiving calls for a shooting in Macy's.
Multiple police departments were called to the scene, including Monroeville Police, Allegheny County Police, Port Authority Police and even Munhall Police, in addition to more departments.
Eventually around 3:30 a.m., police arrested 17-year-old Tarod Thornhill in Brackenridge.
The criminal complaint says police were able to identified Thornhill partially due to a photo on Instagram. They say he posted the photo of himself about four hours before the shooting, wearing the same clothing he's seen in on surveillance footage.
Police say three people were shot, including two men and one woman.
VIDEO: Watch The Police Press Conference
"There were no other injuries besides those three people," said Monroeville Police Chief Doug Cole.
Officials at Forbes Regional Hospital also said they received three shooting victims. Police said Saturday night that two of the victims were in critical condition and the third was in stable condition.
The hospital was in a lockdown situation while the suspect remained at large. Individuals were able to come and go, but there was increased security.
VIDEO: Forbes On Lockdown
Police say one of the male victims was the intended target in the shooting, the other two victims were innocent bystanders.
"So this was not random," Cole said. "We have evidence that leads to that. That we're not going to discuss currently and the investigation is ongoing."
Pittsburgh native and NFL quarterback Terrelle Pryor tweeted after witnessing the scene.
Another source inside the mall, who did not want to be identified, says a guard reported hearing "shots fired" near the Mister Rogers Neighborhood play area.
Shortly after, mall security called to evacuate the entire mall.
VIDEO: Shoppers Describe The Scene:
The mall became a chaotic scene as mall patrons rushed to seek safety.
"I was not expecting to walk out of here tonight passing cops carrying guns," said one woman.
Some shoppers described their experience in the mall when gunfire rang out.
"I was at Pittsburgh Popcorn making a purchase," said Pamela Nichols, "and shots rang out. People started running. And I just ran with the store employees to the back of the room and took cover."
"All of the sudden we heard people screaming," said Athena Coffey of Churchill, "and the next thing you see is a bunch of people, teenagers, scared to death, just exodus en masse in a way you could not believe. I grabbed my children, husband, we started screaming 'go, go, go!'"
Shoppers and employees say they were put on lockdown before being evacuated from the mall.
"There was another little boy, he was like, 'I can't find my mommy, I can't find my mommy,' I grabbed him too," said Coffey.
Police and FBI agents at one point were going door-to-door at shops at the mall looking for suspects.
Police said that there were two officers on detail in the mall when the shooting happened.
In December, the Monroeville Mall closed after a large fight broke out. Reportedly as many as 1,000 people were involved at one point.
The mayor of Monroeville said at the time he would meet with mall officials to work on new security measures.
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