Police descended on Navy Pier on Tuesday afternoon searching for a "disgruntled" ex-employee who shot and killed two men — leaving frantic visitors scrambling for safety in bathrooms and cars.Law enforcement officials at a news briefing outside Navy Pier said they know who they are looking for, but as of 4:15 p.m., the assailant had not been arrested. Investigators are searching for the gunman, who is a former employee of a subcontractor at the pier who was fired Oct. 14, CPD Chief of Patrol Jon Hein said at the news briefing, adding that investigators believe they will have him in custody "soon." Officials did not name the company where he worked. CPD Chief of Patrol John Hein said at a press conference late Tuesday afternoon that the gunman would soon be in custody.Anthony Vazquez/Sun-Times Brian Murphy, chief operating officer of Navy Pier, said the shooting was "targeted," and the wider public was not in danger. Police swarmed Navy Pier on Tuesday afternoon after a gunman opened fire on a loading dock area, killing two people. The gunman remains at large. Police said the attack was targeted and that there was no risk to the wider public.Anthony Vazquez/Sun-Times "At no time did we feel like anybody from the public was in danger, that this was more of a targeted issue that occurred today at Navy Pier," Murphy said.It was about 1:30 p.m. when paramedics were called to the pier, at 600 E. Grand Ave., where they found the two wounded men outside, Chicago Fire Department spokesperson Larry Langford said. Both were taken to Northwestern Memorial Hospital in critical condition, including one who was in "very critical" condition, Langford said. Navy Pier was on lockdown for a couple of hours after a shooting Tuesday.Gina Galinis/Sun-Times A security guard found the victims in a loading dock area, according to scanner traffic. There were shell casings surrounding them.With restaurants, cultural offerings and its famous Ferris Wheel, Navy Pier is traditionally ranked as one of Illinois' top tourist attractions. The state's tourism department, calls it "a civic landmark and one of the top-visited leisure and cultural destinations in the world."But visitors found a different atmosphere Tuesday.Dozens of squad cars raced to the area, and officers — including some with automatic weapons — were seen patrolling the area. A tactical team wearing bulletproof vests and carrying rifles was seen canvassing an area with dumpsters before entering a garage.The pier was put on lockdown, and no one was allowed to enter or exit for a couple of hours. People inside the pier were told to shelter in place.Scanner traffic indicated police were looking for a man who was wearing a white chef's hat, a white chef's jacket and black pants who walked back into Navy Pier after the shooting. Dispatchers said that as of 1:21 p.m. he was seen on video but had possibly changed into a black North Face sweater, white or beige pants and was wearing a black beanie. A witness driving through the pier's parking garage saw several officers, at least one with a gun drawn, looking into cars. Several officers blocked the entrance to the parking garage area. Shortly after 2 p.m., officers told staffers at the Chicago Sun-Times, which has offices inside Navy Pier, to not allow anyone in or out until further notice. Some Navy Pier employees took shelter in their cars, while others hid in a bathroom near one of the ballrooms, according to scanner traffic. Stephanie Knowles was behind the cash register at souvenir shop Oh Yes! Chicago when her manager got a call and said "we got to start closing everything down."They turned off all the lights and the one customer who was in the store at the time was escorted out by police, she said. Employees hid in the back of the storage room until they got the all clear."I was a little nervous, you know, when you think about the high school shootings I've never had to live through that, so this was the closest thing that I've had to that experience," Knowles said.But she says she was able to overcome that nervousness thanks to her fellow coworkers, whom she said are like family, even though she's only been working at the store since the summer. "We kind of kept each other calm," she said.Benjamin Scott, who lives in Logan Square, said he went to Navy Pier to relax after getting off work.“I was enjoying myself listening to music,” he said.Scott saw a bunch of police officers arrive, so he left and was standing near the bus terminal when officers surrounded him, guns drawn. Scott was wearing some clothing that matched one of the suspects, he said. But Scott said he cooperated with police, and they soon let him go. “It’s really scary,” Scott said of the shooting.Jacoyah Harrison, 30, of Calumet City, was at the Pier with her mom to enjoy their day off and celebrate Harrison’s upcoming birthday. They were inside the Flyover when the show was halted. “We were in the middle of it, and then we had to evacuate,” she said. Then “we were greeted by machine guns,” her mom said, referring the police offficers with what appeared to be automatic weapons.Jessica Foster was visiting from Kansas City. She was walking outside and saw a commotion near some dumpsters."I was taking pictures. It was so windy," she said. Foster didn't realize what was going on until she learned there was a shooting and an officer said she needed to leave the area."It was terrifying," Foster said.