Rihanna receives x-rated letters

Rude Boy singer Rihanna is beefing up her security after receiving a string of x-rated letters from a male fan. The singer's boyfriend and friends are worried over her safety.

Singer Rihanna is beefing up her security after receiving a string of x-rated letters from a male fan.

The 22-year-old's boyfriend, baseball star Matt Kemp, is worried for her safety.

"Kemp has asked Rihanna's team to be extra cautious since she was sent two very steamy letters, her friends are also concerned about the situation. They are really worried things with this guy are going to get out of hand," dailystar.co.uk quoted a source as saying.