Two men were fatally shot Tuesday afternoon at Navy Pier by a gunman who authorities believe was a recently terminated worker.

CHICAGO (AP) — A man was arrested Thursday in the fatal shooting of two workers at Chicago's popular Navy Pier tourist attraction. The arrest came after police released surveillance camera images of the man suspected of gaining access to an office space near a loading dock just prior to Tuesday afternoon's shootings, the Chicago Tribune reported.

A man has been arrested for the fatal shooting of two workers at Chicago's Navy Pier. The arrest follows the release of surveillance images. The victims were pronounced dead after the incident. The suspected shooter,

The popular tourist attraction known for its massive ferris wheel was on lockdown for two hours, Illinois police said.

Police believe a disgruntled former co-worker of the victims entered a Navy Pier loading dock and opened fire on Tuesday.

The announcement Thursday afternoon that a person of interest had been apprehended came after surveillance photographs were released showing the gunman — described by police as a "disgruntled," recently fired worker on the lam since Tuesday.