Police say just before midnight Saturday, more than 70 teens and young adults swarmed a 7-Eleven in Silver Spring, Maryland, and walked out with stolen snacks and drinks.
Investigators believe they have identified 22 of the suspects and now have to figure out which ones actually lifted the goods, which ones paid for their items and which ones stood around and watched.
HLN's Prime News spoke to retired FBI agent Steve Moore, who said the store clerk did the right thing by staying out of it.
"If this starts happening, don't interfere with it because you might get killed," Moore said. "It's not worth it."
He says police can help put an end to these 'flash robs' by locking up the perpetrators, which will send a clear message to other teens.