THE thriving black market in illegal New York City food vending permits took a blow on Tuesday morning when six people were arrested as a result of multiple sting operations by the city’s Department of Investigation. Sotirios Econopouly, 71; Fernando Quesnay, 52; Ifigenia Tsatsaronis, 40; Jacob Shimon, 46; Nikhil Dhameliya, 23; and Adamadia Arabatzis, 48, were charged with multiple counts of fraud.

The six were working various angles of the underground market, according to criminal complaints filed Tuesday. Mr. Econopouly, the owner of Steve’s Sheet Metal in Queens, is accused of renting inspection-worthy carts to vendors whose own carts would have failed, then transferring the inspection decals to their carts. Mr. Dhameliya, a notary public, is charged with having notarized blank and pre-signed documents submitted with renewals of permits, which are valid for two years and can be renewed indefinitely by mail.

The probe concluded that at least 500 food-vendor permits of the approximately 3,000 now in circulation in the city are probably held illegally. Some of the permits are in the names of dead people; others are held by people who were no longer working in the vending business. Those cases have been reported to the city’s Health Department, which issues the permits.

The investigation began two years ago, when inspectors at the central Health Department inspection facility in Maspeth, Queens, noticed that the same cart was repeatedly submitted with different documentation.