There's been a spike in pet flipping across the country, when a dog or cat is either stolen or found and then put up for sale online.

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While it may not be common in New Jersey at this point, animal rights activists in the state are offering residents tips on how best to keep their animals safe.

"Anyone who finds a website where people are selling animals should be very cautious," said Investigator Stuart Chaifetz with Showing Animals Respect and Kindness. "Those sites concern us because sometimes people buy those dogs and use them for dog fighting training. Sometimes, you'll get dealers picking them up to sell for animal experimentation. So, as a rule, you should be very cautious about getting dogs from online sites. If you want a dog or cat, go to a shelter."

There are also ways you can protect your dog or cat.

"If you have concerns that your animal may escape, microchipping is a good option. They can be tracked and returned to their rightful owner. You should also be extremely careful with your animal at home. Make sure you're gate is secure, don't let them loose," said Chaifetz. "You just have to be very watchful. Unfortunately, there are people who look at animals as property and they will do anything they can to make money off of them. That's a mindset we have to fight against."

There are many shelters and rescue groups that have legitimate websites.

"If you get an animal for free at a shelter or through a rescue group, that's the best way to stop the people with bad intentions. Once you remove the financial incentive for selling animals, this will stop," said Chaifetz.