Three U.S. tourists were stabbed in Puerto Rico's renowned seaside community of La Perla after being warned not to take pictures. The incident follows a similar attack two years ago when a tourist was killed and set on fire after being warned not to take pictures while buying drugs. The Puerto Rican police are currently investigating the incident and are warning tourists to be aware of their surroundings and to avoid taking pictures of people or places that may be considered off-limits.