There have been five robberies already this year, and many owners fear there will be more.
Security cameras recorded every move in the latest heist of a city jewelry store, last week at Ernesto's on the Upper West Side.
"Yes, they knew exactly what they were doing," said store owner Ernesto Gallardo.
From the second the four thieves entered the store, the camera captures their teamwork.
A woman tries to distract the store clerks while her partners move to the far end of the counter.
One of them removes his coat and places it on the counter. He then leans over showcase, grabs a tray of diamond rings and hides them under his coat.
"Then I realized that was the tray that was missing, I believe he grabbed it put them under the coat, took the coat and left," said Gallardo.
On the same day, another gang struck hours earlier at a Cartier jewelry store on the East Side, resulting in 2 arrests. This follows a string of brazen day-time heists that has store owners fighting back.
November 3rd, thieves smashed a jewelers case with a hammer, but the owner chased them out with a chair. A week later, a jewelry store clerk fought back as armed robbers pushed her to the ground.
"Our recommendation is you don't fight back. You never know what the results will be," said John Kennedy, head of the Jewelers' Security Alliance.
Kennedy says there were 15 major jewelry store heists in the city last year, compared to 5 in 2012. But already in the first month of this year, there have been 5 major hits against city jewelry stores.
"The increase I would attribute to the presence of gangs who commit this type of crime. It only takes one or two gangs to commit all of those crimes," said Kennedy.
The dangers to jewelry store workers are obvious. Robbers shot and wounded the owner at a Queens jewelry store last year. On Thursday, when thieves took $135,000 worth of diamonds from Ernesto's, it was the third time in his career he'd been hit but never hurt, not yet.
"Something has to be done, I don't know, I'm glad I'm alive," said Gallardo.
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