Luka Magnotta, the man accused of killing and dismembering another man in Canada, was arrested at an internet café in Berlin, Germany. But we are now learning that there may have been warning signs.

Animal rights activists and former Playboy models, the Barbi Twins, say they have been looking for Magnotta for years. They say he was the man behind numerous videos uploaded to YouTube that showed him killing kittens.

For more on this story watch Jane Velez-Mitchell weeknights at 7 p.m. ET on HLN.