Justin Bieber was getting snapped after which he snapped … unloading on a paparazzi for saying one thing the pop star felt was disrespectful.

Ya gotta see the heated interplay between Justin and a photog … with the Biebs snapping on the man, set off by the dude saying “Thanks.”

Justin asks the photog — who isn’t a TMZ cameraman — why he is thanking him … and explains why it is disrespectful to take action.

Bieber was heading again to his SUV with Hailey Bieber after grabbing breakfast at Beverly Glen Deli in Los Angeles … and paps have been ready for him.

Justin instructed the man to stay to taking photos and letting him do his factor … without having to thank JB for something.

We do not normally see this type of response from Justin … so it is fairly attention-grabbing.