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Chicago police and fire crews responded about 1:30 p.m. for a report of shots fired in an administrative office near a loading dock in the 600-block of East Grand Avenue, police said in a news conference Tuesday.
A male Levy employee who had been terminated the month before fired the shots, police said.
"As a former employer of the subcontractor, he had access. He knew how to get to that back loading dock area," said Brian Murphy, chief operating officer at Navy Pier.
A 47-year-old man and 51-year-old man, the employee's former coworkers, were shot in the head, police said. They were taken to Northwestern Memorial Hospital in critical condition. They later died, police said.
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Their identities were not immediately released.
Navy Pier was locked down for nearly an hour, but officials called the incident at the popular tourist destination in the middle of the afternoon isolated.
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"We had to lock the entire store down, lock the entire Navy Pier. Everyone was just shutting down. We had customers come into the back," Navy Pier worker Diamond Foster said.
Police have identified a person of interest, who is at large.
A shelter-in-place at Navy Pier was lifted after police determined through security cameras that the shooter had left the area.
"They talking about, 'Alright, everybody be calm, but it's a minor threat," Navy Pier visitor William Wright said. "Everybody really gets started like, a minor threat. This supposed to be Navy Pier."
Police did not say who they were looking for, only that the shooter was a former employee of a sub-contractor at Navy Pier.
There was a large Chicago police response on the north side of the pier near the parking garage. CPD officers in tactical gear were seen in the area about 2 p.m.
"Pulled out automatic weapons, full SWAT gear, the shields, the whole works," Ohio resident Trent Halasek said.
Area detectives are investigating.
No weapon has been recovered, and police remained on the scene about 5 p.m.
Levy issued a statement, saying, "We're absolutely devastated by today's tragic events and the shocking loss of two of our family members. Our hearts break for their families and loved ones, whose lives are forever changed."
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