Seven teenage athletes, who were selected by UK's seven renowned Olympic champions, lit the London 2012 Games cauldron Friday, marking the official start of the games.

The identities of these young athletes were kept a closely guarded secret till the lighting ceremony.

Cameron MacRitchie, 19, Callum Airlie, 17, Jordan Duckitt, 18, Desiree Henry, 16, Katie Kirk, 18, Aidan Reynolds, 18 and Adelle Tracey, 19, lit a single tiny flame on the ground which triggered the ignition of the cauldron's petals.

The concept of the cauldron, designed by Thomas Heatherwick of London, was also kept under wraps till the beginning of the ceremony. The cauldron has 205 copper petals, each one representing the competing nations, which are set to burn till the end of the games.

Delegations of each competing nation were given a copper petal with their country's name and "XXX Olympiad London 2012" inscribed on it. The athletes carried these petals during the parade before placing them down on the ground. The teams will take the petals to their respective countries after the games.

David Beckham brought the Olympic torch to the stadium, which was received by five-time Olympic gold medalist rower Sir Steve Redgrave. Redgrave and the six other Olympic champions, who selected the seven young athletes, passed the flame to the teenagers.

MacRitchie,an upcoming rower was selected by Redgrave, Airlie, young sailor was selected by Olympic Gold-medal winning sailor Shirley Robertson, gold medal winning Swimmer Duncan Goodhew nominated Duckitt.

Decathlete Henry was selected by gold medalist Daley Thompson, Pentathlete gold medal winner Dame Mary Peters opted for runner Kirk, Long jumper Lynn Davies chose javelin thrower Reynolds and runner Tracey was Dame Kelly Holmes' choice to ignite the flame.