In Hong Kong Protests, Faces Become Weapons

They grabbed his jaw to force his head in front of his iPhone. It all failed: Mr. Cheung had disabled his phone's facial-recognition login with a quick button mash as soon as they grabbed him. As Hong Kong convulses amid weeks of protests, demonstrators and the police have turned identity into a weapon. The authorities are tracking protest leaders online and seeking their phones. Many protesters now cover their faces, and they fear that the police are using cameras and possibly other tools to single out targets for arrest.