BERN, Switzerland – Drug maker Novartis AG said Tuesday that animal rights activists have stolen the ashes of its CEO's mother and set fire to his Austrian hunting lodge. Swiss authorities, however, said they didn't know who was behind the attacks. In the latest incident, CEO Daniel Vasella's Tyrollean lodge in Bach, Austria, was badly burned early Monday morning. "It was arson with a professional fire accelerator," Novartis spokeswoman Isabel Guerra said in Basel.