Fireworks explode over the Olympic Stadium at the closing ceremony of the 2012 Summer Olympics, Monday, Aug. 13, 2012, in London. (AP Photo/Ben Curtis)

In this photo taken with a fisheye lens, pyrotechnics light up the sky above the Olympic Stadium during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Julio Cortez)

This image taken with a fisheye lens shows fireworks during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Charlie Riedel)

Fireworks light up the Olympic Stadium marking the end of the the Closing Ceremony at the 2012 Summer Olympics, Monday, Aug. 13, 2012, in London. (AP Photo/Hassan Ammar)

Fireworks go off during the closing ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Andrew Medichini)

Athletes enter the Olympic Stadium during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/David J. Phillip)

The mayor of Rio de Janeiro Eduardo Paes waves the Olympic flag after it was handed to him by President of the International Olympic Committee Jacques Rogge, not seen, during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Matt Dunham)

The Spice Girls perform during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Kristy Wigglesworth)

British singer George Michael performs during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Matt Slocum)

Fatboy Slim performs during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Kristy Wigglesworth)

The Who guitarist Pete Townsend, right, and singer Roger Daltrey perform during the Closing Ceremony at the 2012 Summer Olympics, Monday, Aug. 13, 2012, in London. (AP Photo/Matt Slocum)

British singer Jessie J, second left, performs during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Matt Slocum)

United States' Kobe Bryant reacts after a dunk during a men's gold medal basketball game against Spain at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Eric Gay)

United States' LeBron James and Kevin Durant react during the men's gold medal basketball game against Spain at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. USA won 107-100. (AP Photo/Charles Krupa)

Spain's Marc Gasol dives at the feet of United States' Kobe Bryant for the basketball during the men's gold medal basketball game at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Matt Slocum)

Gold-medalist Stephen Kiprotich of Uganda finishes the men's marathon at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Mike Groll)

Uganda's Stephen Kiprotich celebrates after crossing the finish line to win gold in the men's marathon at the 2012 Summer Olympics Sunday, Aug. 12, 2012 in London. (AP Photo/Anja Niedringhaus)

Athletes run through the Leadenhall Market during the men's marathon at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Lefteris Pitarakis)

The team from Russia performs during the rhythmic gymnastics group all-around final at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Julie Jacobson)

Sweden's Andreas Nilsson, background challenges France's Luc Abalo, foreground, during their men's handball gold medal match at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Vadim Ghirda)

Sweden's Andreas Nilsson challenges for the ball during their men's handball gold medal match at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Matthias Schrader)

Members of the silver medallist team from Belarus celebrate after results were announced for the rhythmic gymnastics group all-around final at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Gregory Bull)

Italy's Roberto Cammarelle, right, fights Britain's Anthony Joshua in a super heavyweight over 91-kg gold medal boxing match at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. Joshua won the gold medal and Cammarelle won the silver. (AP Photo/Patrick Semansky)

Sarolta Kovacs, of Hungary, gets up after falling off her horse All Rise, during the equestrian show jumping stage of the women's modern pentathlon at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/David Goldman)

Yane Marques, of Brazil, pats her horse Over The Odds after completing the course in the equestrian show jumping stage of the women's modern pentathlon at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/David Goldman)

Croatia coach Ratko Rudic swims after jumping in the pool to celebrate his team's 8-6 victory over Italy during the men's water polo gold medal match at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Julio Cortez)

Laura Asadauskaite, of Lithuania, right, is embraced by Anastasiya Prokopenko, of Belarus, after Asadauskaite won the gold medal in the women's modern pentathlon at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/David Goldman)