By Ko Dong-hwan

Kangwon University's student union has apologized for a controversial milk-drinking contest that involved explicit sexual behavior.

During the contest, which featured couples, each female had to lie on a table while her male partner licked milk being poured on top of the woman.

The team that finished consuming the milk fastest won.

The contest presented sexually explicit scenes, as some males licked their partners' bodies or shoved their heads inside their clothes.

An unknown person filmed the scenes and posted them on the Internet.

The student union apologized on the university's student community blog on Saturday.

"The contest has been running for 36 years to promote the importance of health and milk consumption among our students," the apology said.

"We apologize that this has caused some inappropriate scenes due to participants being immersed rather too much in the game."

The student body admitted it was responsible for tainting the university's reputation, and pledged never to do this again.

The contest was part of an annual festival at the Chuncheon campus on Wednesday.