HOLLYWOOD, Florida (CNN) -- Walking around a Florida strip mall, it didn't take long to find shoppers doing exactly what police say is the wrong thing to avoid having holiday gifts stolen.
Police say not to leave items visible in your car.
In one parking area, in plain view on the front seats of cars, were cell phones, portable DVD players and even a woman's purse.
The owner of the purse exited a store, and her embarrassment was evident when she reached her vehicle.
"Can I go away?" she asked, bowing her head. "I know. It's stupid. I'm an idiot." Watch cops carry out Operation Reindeer »
Police prefer to call her an easy target. All over the country, police are running holiday surveillance operations at malls and other areas because they know people are preoccupied while shopping and not thinking about their safety.
Some police departments use watch towers with blackened glass to see high and far. But police say no technology can replace common sense.
"They are leaving things right out in plain view," said Lt. Norris Redding of the Hollywood, Florida, Police Department. "You're buying all these wonderful gifts for people, but yet you put them in the car, and the bad guys are out doing their Christmas shopping."
CNN went on patrol with Redding's "crime suppression unit," watching shoppers leaving stores and seeing how people create opportunities for thieves.
A mother and her two children exited a Kmart, and Redding watched with a keen eye to see what they were doing wrong.
"You see how the kids are just running back and forth? You have the daughter that's about five steps in front of the mother. The little son is behind the basket; she's pulling the basket. It's not a safe way to do things," he said.
"She doesn't even have the keys ready. Now, when she gets to the car, it's going to take her extra time. That's what we talk about. Be prepared, so when you arrive at your car, you're ready to get in."
Another one of Redding's safety tips is to encourage everyone to get in the same side of the car, especially when traveling with children. Keep your children within eyeshot and close by, police say.
Redding approached the family.
"I don't know if you have an alarm on your car," he said.
"I do," the mother replied.
"Well, try and punch it just before you get to [the car] so your doors and everything will already be open," he told her.
Redding said one of the simpler precautions is not to take out all of your cash when making a purchase. Using cash, he said, also increases your chance of being targeted.
As night fell, police continued their surveillance. They looked for people driving around, circling parking lots, doing things they consider abnormal. Police said safety is their No. 1 concern.
One family split up, leaving an elderly man on his own. According to police, that's a no-no because crooks prey on senior citizens. "He has to be at least 75 or 80 years old. Now, he's a potential victim," Redding said.
So Redding approached this family, too. "Stay with him," he urged. E-mail to a friend