Military families in San Diego's Paradise Valley area woke up to a string of vehicle burglaries on their streets Sunday – an unwelcome Memorial Day weekend surprise.

San Diego Police Sgt. Michael Stirk said phone calls started trickling in from people in the Bayview Hills Military Housing complex who found their vehicle doors wide open in their driveways Sunday morning.

"The unfortunate part is the men and the women of the United States military were made victims, which is disappointing, but anybody that's a victim is disappointing regardless of the day," said Stirk.

Various items were taken from at least 15 vehicles, but the stolen items were so inconsistent, it’s hard to define what the burglar or burglars were targeting, Stirk said.

The vehicles hit were parked along Coral Sea Road, Pacific Mist Road and Court and Conch Shell Court.

Herman Coleman, a sailor in the Navy, said two of his vehicles were tampered with, but the thieves did not take anything of value: just a garage door opener and a knife.

Another woman who did not want to be identified said the thieves stole her garage door opener but left her laptop in her car.

Right now, police believe at least 12 people were the victims of these vehicle break-ins.

It’s unclear how the burglars got inside or if they overcame security alarms, and the total value of the stolen items has not been tallied. The weekend car spree wasn't the first time crime has hit the area.

"I think it's really sad that people are preying upon the military, and this neighborhood seems to be an easy target,” said Dan Murphy, a military spouse who’s had his house and vehicle broken into in the past.

Stirk told NBC 7 investigators do not want to release information about the suspected burglars at this point in the investigation.