Katy Perry wore a disguise as she partied over Memorial Day weekend. The singer was eager to celebrate the holiday which honours war veterans and is also viewed as the unofficial start of summer. Katy and a group of friends were seen letting off steam at \"raucous club\" South Pointe in The Hamptons, New York, on Saturday night. To ensure she could enjoy the night without being hounded by fans, she donned a huge hat and glasses. \"It was hard to recognise Katy because she had on an oversize beach hat, with big glasses and a long baggy dress,\" a source told New York Post. Katy and her pals began the evening \"outside in a cabana\". However, they later decided to get closer to the action and asked to move to a table near the DJ, Chris Lake. The 27-year-old star - who is recently believed to have split from Florence + The Machine guitarist Robert Ackroyd - then happily continued to dance into the early hours.