Two gun-toting bicycle riders rode up to a man walking on a street in Westbury on Thursday night, displayed their handguns and robbed him, police said.
Then, Nassau County police said, they rode off.
Police are searching for the two bike bandits and are asking for the public's help.
Police said the robbery happened at about 8 p.m. on Prospect Avenue at Maplewood Drive. The victim, a 30-year-old man, told police he was approached by the bicyclists, who then demanded money. The victim told police the two men lifted their jackets to reveal black handguns tucked into their waistbands.
The robbers then pushed the victim to the ground, rifled his pockets and took $20, police said.
One of the suspects rode a chrome-colored bike and was described as being 18 to 21 years old, police said, the other suspect was riding a black bicycle.
Police ask anyone with information about the robbery to call Crime Stoppers at 800-244-TIPS. All calls will remain confidential.