It happened on Broadhollow Road in Melville around 9 a.m., with the crane crashing into a building that houses an accounting firm.
Fortunately, none of the 15 employees inside was injured.
A company called "MCN Distributors" out of Islandia was apparently removing two air conditioner/heating units and delivering new ones at the time.
The Occupational Safety and Health Administration (OSHA) is on scene.
It is unclear what caused the crane to tip over.
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