LOS ANGELES — Good Samaritans, temperature guns and tougher laws are the newest tools in the campaign to keep animals out of hot cars, where just minutes can mean death.

More calls are coming in about overheated dogs — and officials say that's a good thing, because more people are aware of the problem and calling before it's too late.

Still, despite annual warnings, pets continue to die or suffer serious injury in hot cars. Before summer was even two days old this year, The Associated Press reported the deaths of five dogs in hot cars in Oregon, Massachusetts and New Hampshire.

No one keeps tabs on annual deaths or injuries because so many different agencies handle calls. But agencies say calls have increased to 911, police departments, fire departments, animal control officers, shelters or veterinarians.

The Los Angeles Police Department's Animal Cruelty Task Force has been swamped with calls about pets in unattended cars since summer started and already has seven cases pending prosecution, said task force member Tami Shepphird, an animal control officer with Los Angeles Animal Services.

People running errands are the most common offenders, but they aren't the only ones, said LAPD Officer Jim Cherrette, also a task force member. The homeless will keep pets in cars, he said. Sometimes people will have to move into an apartment where they can't have a pet, so they will keep it in a car, Shepphird said.

"It's more a crime of negligence than malice," Cherrette said.

Studies show that the temperature in a car — even on a mild day — can go up 34 degrees in just 30 minutes.

Heatstroke affects every organ in the body, said Dr. Ben Brainard, an associate professor of critical care who helps run the emergency room for the University of Georgia's College of Veterinary Medicine.

As a dog begins to get hot, it will become anxious, agitated and start pacing, Brainard said, which heats the dog even more. Then the dog will start drooling, maybe frothing at the mouth, vomiting and defecating, the veterinarian said. As the heat starts to affect the dog's brain, it will stumble, lose its balance and have trouble standing. It will then collapse, and finally lose consciousness, Brainard said.

Fourteen states as of 2010 had laws that specifically prohibit leaving an animal in a confined vehicle if it endangers an animal's life, according to the Animal Legal and Historical Center at Michigan State University College of Law. Other states handle deaths and injury under animal cruelty statutes, the college said.

Confronting an animal owner can be dangerous, so a bystander should call police, contact a security guard or mall manager or some second party, said Yvette Smith, an animal control officer and another member of the task force.

If you are able to reach an overheated dog, use water to cool it off. "If the dog is nonresponsive, get it wet and head to the vet," Brainard said.

Police and animal control officers in California can treat hot cars like crime scenes. That means taking photos, collecting evidence and all the paperwork.

One of the best tools to come along is the temperature gun, which can measure the temperature from outside the car. In Los Angeles, animal control officers use them and police hope to get them soon to help prosecute dog owners when the cops or animal control arrive too late.

Depending on the dog's condition, California police can break the window, wait for a tow-truck driver to do it, seize the pet, write a citation or issue a warning if the owner shows up.

"Our goal isn't to put people in jail but to keep animals from dying in cars," Shepphird said.