Tufts University PhD student Rumeysa Ozturk was walking alone Tuesday night to meet friends at a dinner where they would break their 13-hour Ramadan fast when six plainclothes officers suddenly encircled her on the street near her apartment in Somerville, Massachusetts, surveillance video shows. The 30-year-old shrieked in fear when an officer in a hooded sweatshirt and hat grabbed her by the wrists as another pulled out a concealed badge on a lanyard and confiscated her cell phone. Soon afterward, the swarm of officers who had surrounded her on the sidewalk pulled cloth coverings over their mouths and noses, some...