Elton John celebrates 70th birthday with star-studded party

The guest list included Stevie Wonder, Katy Perry and Lady Gaga.

At one point during the party, Wonder performed his iconic rendition of "Happy Birthday" with help from Lady Gaga.

Other celebrities attended the gala, which also served as a benefit for the Elton John AIDS Foundation and the Hammer Museum at UCLA.

John also took to the piano to perform at the party.