A spokesman for the Ministry of Defence said on Thursday that Rain, 30, one of South Korea's best known stars, had admitted the uniform violation. His punishment will be decided next week.

No one at Rain's agency or his record company was available for comment. South Korean men have to do about two years' military service.

The singer, whose real name is Jung Ji-hoon and whose 2004 album "It's Raining" sold a million copies, has also faced complaints over his days off.

During the 450 days of military service he has served so far, the ministry said Rain had taken 94 off while ordinary soldiers would get 50 at most.

Thousands of people, most of them men, have signed an online complaint after seeing pictures of Rain out and about with Kim, 32, billed as South Korea's most beautiful woman, demanding to know whether he was getting special treatment.

Rain is not the first South Korean singer to run into trouble over his military service.

Psy, whose "Gangnam Style" dance shot to global fame in 2012, had to do his military service twice after being accused of neglecting his duties.

Rain debuted in 2002 as a singer and also appeared in Hollywood movies like "Ninja Assassin" and "Speed Racer". His army conscription ends on July 10.

(Reporting By Jane Chung; Editing by David Chance and Nick Macfie)

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