Sunderland chairman Stewart Donald has condemned the small group of Black Cats fans filmed singing a "hurtful and embarrassing" song about former Wales boss Gary Speed.
The former midfielder, who played 213 games for Sunderland's bitter rivals Newcastle United during a distinguished playing career, took his own life in 2011 on a day that shocked the footballing world.
A video has surfaced on social media showing a small group of supporters seemingly mocking Speed's death and private life, and has received widespread condemnation from fans.
Sunderland chief Donald was alerted to the post on Twitter, and suggested the club will take further action against those involved.
"It is shocking," he tweeted.
"I have seen it and I absolutely gutted. It is unacceptable, unjustifiable, wrong, hurtful and embarrassing.
"Gary Speed’s poor family deserve support and understanding and to abuse such a tragic event is simply wrong and sick.
"I’m sorry and I’m on it."
