A passenger who is not wearing pants waits for a subway train during the “No Pants Subway Ride” in Mexico City, Mexico, February 21, 2016. The event is an annual flash mob and occurs in different cities around the world, according to its organisers. (Photo by Carlos Jasso/Reuters)





Passengers not wearing pants stand in a subway train during the “No Pants Subway Ride” in Mexico City, Mexico, February 21, 2016. (Photo by Carlos Jasso/Reuters)





A passenger takes off his pants as others not wearing pants dance while waiting for a subway train during the “No Pants Subway Ride” in Mexico City, Mexico, February 21, 2016. (Photo by Carlos Jasso/Reuters)





A passenger with a superhero mask plays inside a subway train during the “No Pants Subway Ride” in Mexico City, Mexico, February 21, 2016. (Photo by Carlos Jasso/Reuters)





A passenger stands without pants inside the subway as people walk pass during the “No Pants Subway Ride” in Mexico City, Mexico, February 21, 2016. (Photo by Carlos Jasso/Reuters)





A passenger not wearing pants waits for a subway train during the “No Pants Subway Ride” in Mexico City, Mexico, February 21, 2016. (Photo by Carlos Jasso/Reuters)





A passenger not wearing pants waits for a subway train during the “No Pants Subway Ride” in Mexico City, Mexico, February 21, 2016. (Photo by Carlos Jasso/Reuters)





Passengers not wearing pants stand is a subway train during the “No Pants Subway Ride” in Mexico City, Mexico, February 21, 2016. (Photo by Carlos Jasso/Reuters)





A passenger not wearing pants dance waits for a subway train as others laugh during the “No Pants Subway Ride” in Mexico City, Mexico, February 21, 2016. (Photo by Carlos Jasso/Reuters)





A passenger not wearing pants stands as he reads a book inside a subway train during the “No Pants Subway Ride” in Mexico City, Mexico, February 21, 2016. (Photo by Carlos Jasso/Reuters)