Russell Simmons and his girlfriend, Hana Nitsche, are refusing to pay the $5,000 reward for the return of her lost dog, Ivy, saying they’re victims of a high-profile dognapping.

The Carranza family of Palmdale, Calif., claims it found the chihuahua and offered her peaceful return, but Nitsche showed up with the Bodyguard Group of Beverly Hills, who busted in to retrieve the pup.

Richard Davis, a director at the security group that employs veterans, tells us the family weren’t good Samaritans, saying they called Nitsche using a voice disguiser, threatened her and didn’t identify themselves until the reward was offered. They also asked for the cash to be left at one location with the dog pick-up at another.

“We [had] been passive because we [didn’t] want them to kill the dog . . . they told her [Nitsche] has to come alone; no police,” Davis said. “The Bodyguard Group of Beverly Hills, 100% Navy SEAL & U.S. Veterans found kidnapped dog !” Simmons tweeted Saturday. But the Carranzas maintain their innocence, saying, “We were just trying to be good people.”