Police were called to the scene of the Shell station near 36th Street and 5th Avenue around 9:30 a.m.
Authorities say a 25-year-old delivery worker was putting gas in his black moped when he was approached by the suspects who demanded the vehicle. When he refused, he was stabbed in the arm.
A 34-year-old man nearby rushed over to help and was also stabbed once in the back and left thigh.
Witnesses helped the victims until emergency crews arrived.
Both victims were taken to the hospital and are expected to be OK.
The suspects are described as two men in their 20s wearing black masks, black sweaters and jeans.
They fled westbound on 36th Street on a red moped.
A gas station employee said he is disturbed by what happened - especially since the Shell is across the street from PS 958, an elementary school.
"I feel very sad, this is a big problem," said Md Afsur.
So far no arrests have been made.
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