A man wearing a mask waits to take part in a flash mob named "Halloween bike ride" before touring around the city in Madrid, Tuesday, Oct. 31, 2012. (AP Photo/Daniel Ochoa de Olza)

 

              A man wearing a mask waits to take part in a flash mob named "Halloween bike ride"  before touring around the city in Madrid, Tuesday, Oct. 31, 2012.  (AP Photo/Daniel Ochoa de Olza)
A man wearing a mask waits to take part in a flash mob named "Halloween bike ride" before touring around the city in Madrid, Tuesday, Oct. 31, 2012. (AP Photo/Daniel Ochoa de Olza)
Tags: Mob