NEW YORK (CBSNewYork) -- A string of burglaries on the Upper East Side had police warning residents Thursday about a popular deadbolt feature that they say may be giving people a false sense of security.
As CBS2's Tony Aiello reported, people think they are locking their doors – but it turns out they are doing it all wrong.
Ten apartments have been ransacked within the last five weeks, with the suspect or suspects striking at all hours of the day. The NYPD said the burglaries happened from 7:45 in the morning through midnight, and the burglar has targeted walk-up buildings.
The victims all live on the Upper East Side in apartments between East 82nd and East 92nd streets between Lexington and First avenues.
Warning signs are posted all over the neighborhood.
"I know there are a lot of young people who live here, young affluent people, so they probably have good things to steal, it's a shame it's happening in this nice neighborhood," one woman said.
"You have a lot of out-of-towners who have come from areas where they don't worry about their doors so much," one man said. "Let's hope that they do something about it."
The NYPD said residents were locking their doors. But locksmith Mike Khiyayev said the apartments were not secure.
"People rushing to work, they just shut their doors and they think that they're locked, but they're not really locked," Khiyayev said.
Police said the victims were setting the lock buttons on the faceplate for a slam lock. Bu tit takes minimal skill to learn how to use a piece of plastic to jimmy the slam lock and open the door.
That is what the burglars have been doing.
Khiyayev said the answer is always to turn the deadbolt.
"They need to be bolted – you need to insert the key manually, turn it, and lock it. That's when it's secured," he said.
One burglar forced open a door to an apartment on 85th Street. The victim said the burglar took some of his electronic devices, Ray-Ban sunglasses, and his class ring -- as well as his passport and his Social Security card. He is now worried about identity theft.
The laundry list of stolen items also includes Louis Vuitton purses, David Yurman and Swarovski jewelry, and loose rubies and diamonds.
Another resident said her son often closes the door without setting the deadbolt.
"The bottom lock is locked. It's just that he doesn't always close the top lock," she said.
But after the burglaries, that is changing. others are also taking precuations.
"They have these guard things that you can put on your door to prevent someone using a credit card but you just have to be vigilant," resident Bo Montgomery said. "Watch who's coming in behind you, if it's not a familiar face then... just go somewhere else."
Police also recommend replacing standard locks with high-security locks. They have keys with extra security measures to prevent unauthorized duplication.
Police say the last victim in the string of burglaries was home when the suspect walked into his apartment on East 91st Street and Second Avenue, but when they realized there was someone inside, the suspect bolted.
The break-ins have also happened when residents left windows unlocked next to fire escapes, 1010 WINS' Sonia Rincon reported.
No injuries have been reported.
Police aren't sure if more than one person is responsible.
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