The opening ceremony was held in the evening of April 30, 2010, with the attendance of dozens of world leaders. The ceremony consisted of an indoor and outdoor component. Jackie Chan, Lang Lang, and Andrea Bocelli were among the performers in the indoor component. The event featured an outdoor display of fireworks, lasers, and dancing fountains after a performance by singers and dancers. The outdoor ceremony was produced by David Atkins Enterprises. 6,000 LED balls were floated into the Huangpu river representing fish. Organisers called the outdoor show "the largest searchlight display in history, the largest collection of multi-coloured laser firepower ever assembled in one place, the world’s largest LED screen, one of the largest dancing water fountains ever, and the “largest light show ever attempted”." President Hu Jintao declared the opening of the Shanghai World Expo.