It happened Sunday in the Clean Laundryland Laundromat in Williamsbridge.
As one suspect repeatedly punched a worker, two other suspects struck him with a stick.
After the worker was chased out of the building, the four suspects stole the cash register and took off.
So far there are no arrests. Police say they are looking for two men and two women.
Anyone with information in regard to this incident is asked to call Crime Stoppers at 1-800-577-TIPS (8477).
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