As of late Tuesday, police were still seeking a person of interest. Belmont Area detectives remained at the scene ...

Police believe a disgruntled employee was responsible for the shooting that killed two people on a loading dock at Navy Pier.

Although police said the incident happened in an office space of a loading dock, not in a public area. "As a former employer of the subcontractor, he had access," Navy Pier COO Brian Murphy said.

Some people who were in indoor areas of Navy Pier did not hear the gunshots. But when they stepped outside and saw such a police presence, it became clear something serious had taken place.