Former girl group member Shoo of S.E.S. is under investigation for failing to pay back hundreds of millions of won in debt which she used to gamble.

The criminal division of the Seoul Eastern District Prosecutors’ Office said Friday they are looking into allegations that Shoo, whose real name is Yoo Soo-young, borrowed money from two people at a casino at Walkerhill Hotel in Seoul in June.

The two people who lent her 350 million won and 250 million won, respectively, sued her for not paying back.

As they claimed that Shoo borrowed the money to gamble, prosecutors are considering gambling charges against her.

Gambling is against the law for Korean citizens in most places. A handful casinos operating in Korea are open only to non-Korean citizens.

It is believed that Walkerhill allowed her in because she had permanent residency overseas.

Shoo, a Korean citizen with a US green card, apologized to her fans through an online media interview on Friday saying that she didn’t even know green card holders could enter the casino until she got there, after initially denying that the “37-year-old former idol star with a foreign passport” in media reports was her.

By Kim So-hyun (sophie@heraldcorp.com)