US security chief Markwayne Mullin said the tournament will be "very secure" but said "lone wolf" attacks remain a concern.

LOS ANGELES, June 10 : Security planners for the World Cup are preparing for drones to pose one of the tournament's most complicated threats, as officials seek to protect…

US security chief Markwayne Mullin said the tournament will be "very secure" but said "lone wolf" attacks remain a concern.