CHICAGO (CBS) — A cruise from Navy Pier was called off Wednesday night, after threatening notes were found saying a bomb was going to blow up onboard.

Employees of the Spirit of Chicago cruise ship found the first note claiming a bomb would explode after 3 p.m. on a gangplank, a police Bomb and Arson sergeant said. No passengers were aboard the ship at the time.

After searching the ship, police found another note with a similar message, the sergeant said. No explosives or other suspicious items were found on the ship.

No one was injured, and no one was reported in custody as of Thursday morning.

No one was immediately available for comment from Entertainment Cruises, which operates the Spirit of Chicago, Odyssey, Mystic Blue and Sea Dog cruise ships.

The Sun-Times Media Wire contributed to this report.

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