The shooting happened at approximately 8:15 a.m. Monday at the New Castle County Court of Common Pleas, located at 500 N King Street.
According to Wilmington police, two women were killed in the incident. The alleged shooter, a male, is also dead.
The identity of the gunman is not known at this time.
Local and federal authorities responded to the scene. The courthouse was evacuated and officers are conducting a search of the building.
Stay with Action News and 6abc.com as more information becomes available.