Selena Gomez, Katy Perry attend UNICEF SnowFlake Ball

Selena Gomez and Katy Perry were among the guests at the 2010 UNICEF SnowFlake Ball at Cipriani 42nd Street on Tuesday night.

The black-tie gala celebrated the lighting of the UNICEF Snowflakes on New York's Fifh Aveue  and honored those whose philanthropic commitments support its mission to save children's lives.

Gomez tweeted that she was "proud" to be a part of the event :

The guests were all dressed up for the occasion. Katy Perry wore a navy Naeem Khan caped ensemble and "Girls" star Allison Williams also wore Naeem Khan. Gomez wore a black and gold gown by Dolce & Gabanna and Uma Thurman wore a dark blue gown by Atelier Versace.