There have been at least seven incidents during August and September, targeting men walking on the street.
In several cases, police say the victims were approached by the suspects and struck about the head and body before their belongings were stolen.
The items taken include cash, wallets, knapsacks, cell phones and jewelry. The attackers fled on foot after the robberies. The total value of the property stolen was nearly $9,000.
One man was knocked unconscious during one of the assaults, but no other serious injuries were reported.
The suspects are described as black males, 20-30 years of age, last seen wearing all dark clothing.
Anyone with information about the suspect is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477) or for Spanish, 1-888-57-PISTA (74782).
Tips can also be submitted by visiting the CrimeStoppers website or Twitter @NYPDTips.
All calls are kept confidential.
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