Three of the men were struck in the leg and one was hit in the hand during the shooting at 10:30 a.m., police said. It appears that the gunman ran from around the corner and opened fire.
He then ran away, possibly going into the subway system.
Three of the victims were 31 years old. The fourth victim is believed to be 35.
SkyFox was over the area east of Nostrand Avenue as police cordoned off the mostly commercial and busy street.
The conditions of the victims were not clear but they were all expected to survive. A description of the shooter was not released.