UEFA has opened disciplinary proceedings against Chelsea following allegations their fans sang anti-Semetic songs during the club's Europa League clash with MOL Vidi in December.
The incidents, which occurred just days after four Chelsea fans were suspended by the club after claims they racially abused Manchester City forward Raheem Sterling during the Premier League clash at Stamford Bridge, are said to have taken place during the 2-2 draw on December 13.
Chelsea reacted angrily at the time, releasing a statement denouncing those allegedly involved.
It read: "Anti-Semitism and any kind of racial or religious hatred is abhorrent to this club and the overwhelming majority of our fans.
"It has no place at Chelsea or in any of our communities.
"Any individuals that can't summon the brainpower to comprehend this simple message and are found to have shamed the club by used using anti-Semitic or racist words or actions will face the strongest possible action from the club."
UEFA's Control, Ethics and Disciplinary Body will deal with this case at its next meeting on February 28, 2019.