Santa’s got reindeer watching his sleigh, but shoppers at the mall best lock their cars and keep gifts out of plain sight, police say.

With the arrival of Black Friday, the heralded start of the holiday shopping season, police in Brookhaven, Buckhead, Dunwoody and Sandy Springs are shifting officers’ assignments and adding patrols to make their presence felt in high-volume shopping areas. Police say they want to be visible throughout the holiday season.

Ralph Woolfolk, a spokesman for the Atlanta police, said the department offers officers overtime opportunities in a program called “Holiday Detail 2014.” That enables the department to keep more officers on the street. In Dunwoody and Brookhaven, police shift officer assignments as the need arises during the holidays.

Police officers will also be out in uniform even when off duty, he said. “Chief [George] Turner requires all APD officers to wear full uniform, with few exceptions, during the holiday season, which enhances visibility throughout the city,” Woolfolk said.

Sandy Springs police spokesman Ron Momon said more police from specialized units are reassigned to shopping areas. “We also typically have some of our community officers and citizen volunteers pass out holiday safety flyers in those areas as well,” Momon added.

Police also are warning holiday shoppers to be careful to protect themselves from thieves.

While increased police presence may deter some criminals and prevent crimes of opportunity, Dunwoody Traffic Enforcement Officer Christopher Irwin said people need to stay aware of their surroundings and take precautions like putting valuables inside the trunk of the car before going shopping (or to a place like a gym, where people commonly lock purses and laptops in trunks).

“People go shopping and they’ll come out and put stuff in their trunk, but what people don’t realize is that the criminals are actually out in the parking lots watching,” Irwin said.

Officer Carlos Nino of Brookhaven said shoppers should let police know if they see anything suspicious. “The public is our extra set of eyes, and if you see something, say something,” he said.

Police said shoppers also need to protect themselves. Busy shopping areas, such as malls, grocery stores and shopping centers, typically increase off-duty officers to provide extra coverage during the holidays, but they can’t be everywhere, officers said.

“The mall does have security; however, you can’t be everywhere at once. ‘Lock, take and hide’ is our motto,” Irwin said.

During a recent morning patrol through the parking lot at Perimeter Mall, Irwin said five to 10 cars at a mall typically display in plain view items thieves want to steal. Some car doors are left unlocked. Criminals will walk through rows of parked cars at the mall, looking inside vehicles for items like laptops, cellphones and electronic gifts, Irwin said.

“That gentleman sitting in his car,” Irwin said, motioning across Perimeter Mall’s parking lot. “He’s typing on his phone. Now, it’s around lunch time so he could be at lunch or he could be looking out for a security guard or a cop to warn people on foot, hypothetically speaking.”

While all police watch for suspicious people around malls and shopping areas, they say people leaving town for the holidays should plan to have their home watched and the mail brought inside. Irwin said residents can go online and ask police to keep an eye on their property.

“This time of year is no different than any other, aside from the fact you have more cyber criminals out there trying to get their fill,” he said.

Joe Gray, a security researcher and consultant, said his best advice for online shoppers is to make sure their antivirus program is up-to-date and that they’re shopping on secure websites, and “definitely don’t shop online in public places like the library.”

Dunwoody Traffic Enforcement Officer Christopher Irwin says people need to stay aware of their surroundings and take precautions.