BY ROBERT POZARYCKI | Four robbers beat up a deliveryman and sprayed him in the face with a chemical while robbing him on a Gramercy street Monday night, police reported. Law enforcement sources said the attack happened at about 9 p.m. on Sept. 30 as the 36-year-old deliveryman dropped off food at an apartment building on East 24th Street near 3rd Avenue. According to authorities, the four bandits approached the deliveryman soon after he arrived on the scene, and demanded that he hand over his iPhone and bicycle. When he refused, cops reported, the group went on the attack, punching the deliveryman in the face. One of the robbers then displayed a knife, while another sprayed the victim with an unknown substance. The four thieves then took the deliveryman’s phone and bicycle and fled eastbound along East 24th Street, authorities said. Officers from the 13th Precinct and EMS units responded to the incident. Paramedics treated the victim at the scene for his injuries. As shown on the Citizen app, numerous police units responded and canvassed the area for the suspects, but the search ended without any arrests made, according to police. Sources familiar with the investigation described the suspects as four Hispanic males. The investigation is ongoing.