Chelsea says a section of its fans "embarrassed" the club by singing and jeering during a minute's silence to pay respects to the 96 victims of the Hillsborough Stadium disaster in 1989 and the death of Livorno midfielder Piermario Morosini.

The jeering occurred before kickoff in Sunday's FA Cup semifinal at Wembley Stadium.

Chelsea released a statement saying the club "is extremely disappointed that a very small minority of fans embarrassed the club today by not honoring the moment's silence."

Interim Chelsea manager Roberto di Matteo added that he was "extremely disappointed" by the fans' actions.

Morosini collapsed and died Saturday after suffering a heart attack during a Serie B game in Italy.