Lyudmila Blonska of Ukraine is under investigation for a positive doping test and could be stripped of her silver medal in the Olympic heptathlon, according to AP.

The International Olympic Committee says it has opened a disciplinary procedure into Blonska, who finished second behind fellow Ukrainian Nataliia Dobrynska last Saturday.

The IOC disciplinary commission and executive board are expected to rule on the case Thursday.

If found guilty of a doping offense, she would lose her medal and be expelled from the games.

The third-place finisher in the heptathlon was American Hyleas Fountain, while Russia`s Tatiana Chernova was fourth.

Four athletes have been disqualified and kicked out of the games so far for positive drug tests.

Blonska served a doping suspension between 2003-05. If found guilty of a second offense, she could face a lifetime ban.