More than 300 clowns are taking part in the 15th Annual International Clown Convention this week in Mexico City. Here are some images from the event. A clown climbs the stairway of the Jimenez Rueda theater to participate in the costume and make up competition of the "XVth International Clown Convention" in Mexico City. A clown plays with a lizard as others laugh while trying to break the "laugh world record" in Mexico City, Wednesday, Oct. 20, 2010. Hundreds of clowns are attending the XVth International Clown Convention in the Mexican capital. Clowns laugh while trying to break the "laugh world record" in Mexico City, Wednesday Oct. 20, 2010.