South Korean pop star Rain left on Tuesday to enlist in mandatory military service that will keep him away from the entertainment industry for 21 months.

"Thank you for the 10 years of love," Rain told fans and supporters as he left for an army base in Uijeongbu. The 29-year-old singer/actor may be best-known to American fans for his role in the 2009 film 'Ninja Assassin,' which won him an MTV Movie Award in the Biggest Bada--- category.

Rain joins a number of Korean singers who have been forced to interrupt their careers for military service. While some Olympic athletes receive an exemption from the country's requirement that all males must serve, entertainers are not granted special treatment.

At 29, Rain is enlisting later in life than most of his fellow countrymen. Fans are disappointed to lose their favorite star for two years, but the move could end up helping his image and keeping his career alive when he returns. Rain also appeared in the 2008 film 'Speed Racer.'