Investigators said it was a disgruntled former employee who opened fire at Navy Pier.
Police said that employee was fired back on October 14.
He returned to Navy Pier around 1:30 p.m. Tuesday while it was filled with tourists and shot and killed two of his former co-workers, 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.
One of the victims has been identified to the Cook County Medical Examiner's Office as 51-year-old Lamont Johnson.
That shooting caused the pier to go under a short lockdown. Although police said the shooting happened in an office space of a loading dock not in a public area.
"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.
Levy confirmed the victims worked for the restaurant and hospitality company, saying in a statement in part, "Our hearts break for their families and loved ones, whose lives are forever changed."
Investigators said they know who they're looking for but have not released a name of the suspect.
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