SAN FRANCISCO (KGO) -- There's a warning for parents from the head of the San Francisco FBI, Sanjay Vimani, about an international network of predators called "764" that's using seemingly innocent ...

Authorities have been using canines, drones and helicopters to search for Hardin ... and he also knew of caves in the area, former FBI executive Chris Swecker, who led the agency’s Charlotte ...

Hardin’s DNA was entered into the FBI’s Combined DNA Index System ... Authorities are using canines, drones and helicopters to search the rugged northern Arkansas terrain, Champion said.