NEW YORK (CBSNewYork) -- The NYPD is looking for four suspects in connection with a series of food cart vendor robberies over a three-hour period in Queens last week.

On Oct. 21, the suspects waved a gun and demanded money from a food cart vendor on Rockaway Parkway and Lefferts Boulevard. The suspects took $300 from the 33-year-old owner and fled the scene, police said. The first incident occurred at around 11:30 p.m.

Less than 90 minutes later, the suspects walked up to another food cart vendor, this time on Liberty Avenue. Again, one of the suspects showed a gun and demanded money. The 44-year-old vendor gave him $200 and the four suspects fled. About two hours after that, the four suspects struck again, demanding money at gunpoint from a vendor at Pitkin and Euclid avenues. The 48-year-old man working that cart handed them $190 and they fled.

Police released surveillance images of the suspects. They may have driven off in a light minivan after the robberies.

Anyone with information in regards to this incident is asked to call the NYPD's Crime Stoppers Hotline at 800-577-TIPS.