For the second time in less than a week, surveillance video caught a group of thieves smashing their way into a jewelry store and making of with thousands of dollars worth of merchandise — and the store's owner believes the incidents may be connected.

The latest incident occurred around 5:30 p.m. Friday in Brooklyn. Video showed the trio of thieves take a sledgehammer to the front window of the jewelry store on Liberty Avenue in East New York.

The robbers take everything in sight, running off within seconds, video showed. A store worker was seen chasing them down, but by then it was too late, the culprits were gone.

The sledgehammer was left behind at the scene, where broken glass was strewn across the sidewalk hours after the robbery.

"I was inside fixing jewelry and I hear like a bomb. I come out and they smash the window here," said shop owner George Bachour.

He said that the amount stolen was likely in the six figures, up to $150,000.

"They take rings, charms, stuff for Mother's Day, three items with diamonds," he said.

If the incident sounds familiar, that's because it's eerily similar to a robbery in the Bronx on Sunday. In that instance, surveillance video again showed a sledgehammer-wielding thief smash his way through the front window of a jewelry store.

That video, from around 4 p.m. Sunday, shows a man dressed in all black take a sledgehammer to the front window of the M&NP Jewelers store on White Plains Road in the Pelham Parkway section during broad daylight.

"All of a sudden we hear a boom, a loud boom. The last thing I had in my mind was that we were gonna get robbed," said store employee Yailin Reyes, who was working inside at the time and somehow had the presence of mind to run to the front gate and pull it down.

"My first instinct was to close the gate. And while I was closing the gate, the guy got stuck between the glass and the gate, and I was like 'Oh my god am I gonna chop him in half?" Reyes said.

A second robber came to help his friend out, holding the gate up. They weren’t able to get much, but police said the duo did grab 10 gold chains and five gold pendants.

The total loss in that heist was less, about $20,000. Police said that robbery was part of a citywide jewelry store robbery pattern the last few months. At least 18 stores have been hit, with the robbers getting away with more than $247,000 in stolen goods.

In one incident on Fifth Avenue in Manhattan, police said that the same crew broke into a store just a day after the Bronx heist, and got away with more than $187,000 in jewelry.

On Thursday, police announced that one of the suspects in the Bronx robbery had been arrested and charged for their alleged role in the heists. As for Friday's robbery, investigators so far have not connected the case to any of the others, but Bachour believes it is.

"I was worried about this and look, it happened to me," he said. "I check the video from the Bronx the other day — the same hammer, the same way!"