The dumb online video trend of the moment starts with footage of teenagers and 20-somethings walking through the aisles of grocery stores, carrying a gallon jug of milk or juice in each hand.

After a few seconds, the star of the video clip flings the containers into the air, or smashes them on the tiled floor, then performs a pratfall into the pool of liquid as an accomplice records the scene.

It’s called “milk smashing” or “gallon smashing.” It’s a prank that’s trending on YouTube and, to the frustration of law enforcement and store employees, at grocery stores nationally and in Buffalo Niagara.

Tops Markets has seen six of these cases in the last week at its stores in Erie County, while Wegmans has seen three in its area stores over the same period.

“It’s a prank. However, we don’t find it to be amusing,” said Shaun Frank, asset protection manager for Wegmans in Buffalo. “We consider it a crime.”

So far, no one has been reported hurt in any of the local “milk smashing” incidents, but police say the pranksters could face criminal charges, and store officials say they will prosecute anyone they catch in the act.

“Milk smashing” follows in the footsteps of the once-popular “fire in the hole,” in which participants pulled up to a drive-thru restaurant window and threw their drinks at a worker while shouting the aforementioned phrase.

It’s the latest bizarre, food-related prank that has transfixed a segment of the population that apparently has high-tech savvy and too much time on their hands.

“[Online file-sharing] is a great tool. Whenever you have a tool, people will end up using it for other purposes, including a ridiculous one,” said Jeffrey J. McConnell, chairman of the Computer Science Department at Canisius College. “What you have is people using YouTube to get Andy Warhol’s 15 minutes of fame.”

An ABC News report traces the “milk smashing” or “gallon smashing” trend to three teenagers in Northern Virginia. The initial video they recorded received three million views before it was removed by YouTube.

The prank has spread, with a search Tuesday on YouTube for the term “milk smash” bringing up more than 2,900 clips on the video-sharing site.

The smashers in the videos typically end up lying on the floor in the aisle, with milk or juice pooling around them, after pretending to lose their balance. The occasional unlucky shopper can end up splashed by milk, and store employees are stuck cleaning up the mess.

“If their intention was to prank, this isn’t even a really good prank,” said McConnell, who added, “They just look foolish writhing around on the floor.”

Lancaster Police Capt. William Karn said the “milk smashing” pranksters can be charged with criminal mischief, a misdemeanor.

Town police learned about the prank Monday, when a store employee from the Tops at 4777 Transit Road reported a “milk smashing” incident that occurred shortly before 1 a.m. Sunday.

In that case, a man smashed two plastic jugs of milk while a woman recorded the prank on her cellphone, said Karn, whose detectives will study the store’s surveillance video of the incident.

Katie McKenna, a Tops spokeswoman, declined to identify the locations of the five other “smashing” incidents at Tops stores in Erie County over the past week.

“This is destructive behavior. It’s potentially dangerous. It could lead to associate and customer injury. We are taking the matter very seriously,” McKenna said.

Wegmans has had three such incidents, also in the past week, with one at a store on Losson Road in Cheektowaga, one in Erie, Pa., and one apparently at the Alberta Drive location in Amherst, Frank said.

He said contacts in the law enforcement community and in the industry had warned Wegmans officials to prepare for the “milk smashing” trend, so Frank wasn’t surprised when it came to the company’s stores here.

Store security guards, managers and cashiers have been warned to be on the lookout for possible smashers, Frank said.

“If we can prosecute these individuals, we absolutely will prosecute them,” he said.