As police canvassed Oakbrook Center following a shootout at the popular mall just two days before Christmas, several store windows were broken as officers worked to clear the scene.
Shoppers reported being huddled in back rooms as they took cover during the shooting Thursday evening, but as officers went store by store looking for a remaining suspect and other potential victims, numerous store windows were shattered in the process.
"That was just to make sure we're able to gain entry and actually to search that area," Administrative Sergeant Reid Foltyniewicz with the Oak Brook Police Department told NBC 5 Friday. "Some of the places were locked in. No one was left inside, other people were just afraid to come to the door. So we have to get in there because we don't know what we may find. Once again, there may be someone that's a victim that's injured, or even an offender that's injured or there's evidence, so we do need to make entry at some point."
Foltyniewicz said officers worked to clear the large mall following the shootout between gunmen that left one shooter wounded and four bystanders hurt.
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"Every inch of that mall was covered and we released it just before midnight," Foltyniewicz said.
He praised store employees, mall security and responding officers for their response following the unexpected event in the midst of last-minute holiday shopping rushes.
"Unfortunately, we had this real world, you know, this real world scenario because we've trained for this all the time, but not only do we train, the mall security trains, the property management team trains and the employees at the mall all train," he said. "So we even trained together, we host safety seminars, so it was excellent, excellent from all the employees that immediately when this happened stores were locked down, employees knew what to do. They helped, you know, people that were there shopping to get to cover and lock the store and turn the lights off, so excellent job on everyone's part."
Police are searching for a second suspected gunman hours after the shooting first took place.
Two suspects, including one alleged shooter and a "companion" of one of the suspected gunmen, were already in custody as of Thursday evening, but a third person, believed to be the second shooter, was still being sought Friday morning, police said.
Police released images of the suspect they are still looking for early Friday, asking anyone who may recognize him or have additional information on the shootout that sent holiday shoppers running for cover to contact Administrative Sergeant Reid Foltyniewicz via e-mail at RFoltyniewicz@oak-brook.org or phone (630) 368-8746.
Police say that at least five people were injured during the incident Thursday.
According to authorities, a police officer that was working at Nordstrom overheard gunfire at approximately 5:44 p.m. The gunfire originated from a corridor between the store and Ann Taylor, authorities said.
Police say two individuals were seen firing gunshots at one another, sending shoppers fleeing into stores for cover.
An eyewitness told NBC 5 that the mall was placed on lockdown at approximately 6 p.m. because of the incident, and said she was forced to hide in the stockroom of Nordstrom's.
NBC 5's Vi Nguyen was outside of Oakbrook Center shortly after the shooting:
When the officer moved to confront the suspects, they both attempted to run into the Nordstrom store to flee.
Police said one suspect, who was shot at least four times, was hospitalized and is expected to survive. Another suspect was taken into custody while trying to leave the area, authorities said, but one suspected shooter remained at large.
At least three other bystanders were struck by gunfire, according to officials.
A woman in her 40s was shot in the left thigh, another woman in her 40s was shot in the left thigh, and a woman in her 20s was shot in the right foot. A fifth victim, a woman in her 20s, fractured her ankle while fleeing the scene.
More than 100 police officers were at the scene into late Thursday, including multiple SWAT teams. NBC's Sky 5 helicopter observed SWAT teams entering stores as they continued to work to clear the mall.
Brookfield Properties, the management company that runs the mall, issued a statement thanking police for responding to what they termed an “isolated incident.”
“Tonight’s isolated incident is extremely upsetting for our shopping community,” officials said in the statement. “We are grateful for our partners at the Oak Brook Police Department for their diligence in leading this developing investigation.”
The mall was expected to reopen at 10 a.m. Friday with a heightened police presence.
"We've amped up security, we've always had that anyway during this time but even more than usual, so it is completely safe," Foltyniewicz said. "We want people to still enjoy their time, enjoy shopping, having a good time, enjoy spending time with their families and being out there."