One day after UCF announced to media outlets it was investigating a party held by Sigma Chi following student Ann Hefferin’s sudden death, the fraternity lowered its flag to half-staff.

Multiple sources inside the UCF Greek community told KnightNews.com Hefferin attended the party before she died.

KnightNews.com tried confirming whether Sigma Chi was expressing its condolences, but a spokesman from the fraternity’s national office has not returned calls to do so.

Meanwhile, the mystery surrounding what caused the new Delta Delta Delta sorority member’s death continues. KnightNews.com checked in with the Orange County Medical Examiner’s office Friday afternoon and found out it is expected to take about five weeks before toxicology tests are back.

Toxicology reports will show whether alcohol or drugs were in her system, and that information could be used to determine the cause and manner of death, according to the Medical Examiner’s office.

At this point the autopsy’s official status is “pending” and officials said they do not yet know if alcohol played any role in her death at all.

KnightNews.com will continue following this major UCF news. Check back for updates.