The last big bust of a dogfighting ring in the U.S. spanned several Southern states and rescued 367 pit bulls destined for lives of misery and eventually violent deaths.

That was in August 2013. Since then, dog fighting busts have spanned the country, some discovered in drug raids, others revealed as gambling operations, others some combination of both. Animal welfare groups say thousands of dog fighting rings are operating nationwide and that the numbers may be increasing.

But no one can say for sure as neither law enforcement organizations nor animal welfare groups know how many dogs or people were involved in fight rings last year. No one can say with certainty how many people were arrested for organizing — or attending — these fights or if the numbers are more or less than other years. No reliable national statistics about dog fighting are available. In fact, no comprehensive national statistics involving any crimes against animals—torture, physical abuse or neglect—are kept.

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