Pop star Rihanna, who is currently embroiled in an assault case against former boyfriend Chris Brown, is ensnared in a nude-photo scandal, according to online reports.Last Friday, pictures of a woman closely resembling Rihanna (real name Robyn Rihanna Fenty) were leaked on the Internet. A few showed nudity.However, the nude photos do not show a clear shot of her face, said website Gossip Girls. Lawyers at Rihanna's record label, Def Jam, have asked the websites to remove the pictures, calling the photos a violation of "the artist's rights".Rihanna, 21, is said to be so embarrassed she's fled Hollywood and taken refuge in Hawaii. It is yet more misery for the star who in February was allegedly attacked by then boyfriend, singer Chris Brown. Leaked photos revealed shocking injuries to her face. He was charged with assault.One of Rihanna's pals said: "She is freaking out. She was on the road to recovery after a terrible few months. She has no idea how these pictures have been leaked but she's determined to find out." One photo shows a man, believed to be Brown, sitting in the hotel room with a pair of pink pants on his head. Rihanna is recording a new album in Hawaii. Her pal added: "She's rushed off to Hawaii to escape the scrutiny.The Good Girl Gone Bad singer posed for raunchy shots in the January issue of Germany's FHM mag, but preserved her modesty with a strategically placed umbrella.She has insisted in the past that she would never want to be pictured naked, saying: "My mother would kill me if I posed nude."