Last month on a sunny Saturday morning, Lisa Baxter and her fiancé, Mike Janovic, loaded up their three dogs -- a beagle, a Pomeranian and a Chihuahua -- for an outing at the Brook Run Dog Park, an off-leash dog run in Dunwoody, Ga.

They were looking forward to letting their pets exercise and possibly make some new four-legged friends. What they didn't anticipate was a turn of events that would lead to the injury and subsequent death of their 7-year-old Chihuahua, Chi Chi.

"Two of our dogs were roaming off-leash, and Chi Chi was on a leash, as we like to keep him close because of the various sizes of dogs at this park," Baxter said.

Unlike some dog parks, animals are not separated by size at Brook Run, a 4-acre sprawl where dogs can freely run and play. But like all dog parks, visitors enter at their own risk.

According to Baxter, a spaniel mix lunged at Chi Chi and viciously attacked the dog, drawing blood. The spaniel also went after the Pomeranian, but the beagle took cover.

"We were truly shocked that the owner did nothing to help us separate the dogs," Baxter said. "And he fled the scene, never apologizing, nothing."

Although Chi Chi was rushed to the nearby Animal Emergency Center of Sandy Springs, efforts to save the dog were futile, and a few days later, the pup died. Similar tales are all too common, but they don't have to be.

"Dog parks keep us in business," said Dr. Tommy Dempsey, who treated Chi Chi.

Laine Sweezey, president of the Brook Run Dog Park Association Inc., is currently drafting a proposal requesting more land from the park to create a small-dog area. She said the association is also considering providing a ledger so dog owners can report incidents and exchange personal information when the occasion arises.

"We're all dog owners ourselves and will do whatever it takes to make sure nothing like this ever happens again," said Sweezey. "But we understand that all dogs are different and you never know exactly what one might do."

Meanwhile, Sweezey advised dog owners to refrain from leashing their pets at an off-leash park.

"You're opening yourself up to danger," she said. "The leashed dog automatically feels threatened and vulnerable and sends these signals of fear to the other dogs. And that is when they can get attacked."

Most dog parks have rules. The rules at Waggy World Paw Park in Alpharetta, Ga., for example, are clearly marked at the entrance, on fences and on the city's website.

Heeding safety tips can protect dog owners and their pets. A dog should never be left unattended and should be current on its shots and licensing, if required.

It's a bad idea to bring small children or food to a dog park, not even training treats. And if your dog is in an altercation with another pet, do the right thing and exchange information, as it could save the injured dog's life.

"In our case, if we'd had the medical records of the spaniel, the infection that ultimately killed Chi Chi could've been detected from the other dog's shot records," Baxter explained. "We were saddled with thousands of dollars in vet bills. I think we at least deserve an apology."

If your dog gets rough with another dog, leave the park immediately.

"The other pets can be tipped off to your pet's aggression and could make your dog a mark," said Dr. Sarah Bird of the Cumberland Animal Clinic in Smyrna, Ga. "We're not pretending to know exactly what a dog is thinking, but it is always best to err on the side of caution."