Surveillance footage released by the FDNY on Sunday shows the moment a suspected arsonist chucked a Molotov cocktail into a Brooklyn deli on Saturday. Joel Mangal, 38, allegedly carried out the fiery attack at NR Rock Deli in Bedford-Stuyvesant after he got into an argument there with staff, according to the FDNY and law enforcement sources. Footage from outside the deli shows the suspect igniting one of the incendiary devices before tossing it through the front door. The gas bomb struck inside near the deli display case, covering the glass and surrounding areas with flames, according to footage from inside the store. Mangal allegedly tried to throw a second Molotov cocktail into the deli, but was stopped by a witness who smacked the explosive out of his hand, footage shows. Two deli workers fled the store after the attack. One of them suffered non-life threatening injuries, authorities said.