"The problem of fly-grazing - the problem of horses on common land - is an enormous problem" says the RSPCA's Gethin Russell-Jones.
"Our RSPCA inspectors are involved daily in recovering horses, dealing with complaints".
"There must be hundreds and hundreds of horses scattered across South Wales at the moment".
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Pensioner arrested following the death of a woman on the day he stepped onto tracks at Cardiff Central Station.
Walk-on actor John Lewis was jailed for fraudulently claiming £70,000 while working on Casualty and Sherlock.