Dog-Fighting On The Rise?

But Sergeant David Hunt who works undercover in Ohio to stop dog-fighting wouldn't say the sport is becoming more popular.

Sergeant Hunt says, "The biggest problem is the fact that most police officers don't know about it..once they get educated on it..they do become proactive and that's what you're seeing more and more of these days."

Like Hunt many investigators say they'll conceal their identity in order to make dog-fight related arrests - A measure taken by police even here in Tennessee.

Guy Bilyeu with the Hamilton County Humane Society says, "We actually sent someone in with the Soddy Daisy PD to buy a dog and they showed them fighting right there and we had them on an audio tape..all the way through fighting and that's some of the pictures with the dog's ear ripped up."

Investigators say a person's fear to speak out about the illegal activity often makes their job more difficult.

Lt. Mark Timmis investigates dog fights in Texas. "They see the dog fighting and they tell them, we'll hurt you if you tell people about this," Timmis said.