Sheffield United have banned a number of supporters following their behaviour during the December clash with Bradford City.
The club launched an internal investigation after a number of smoke bombs were thrown by fans during the 3-1 win on December 28, while additional inappropriate language and behaviour was reported at Bramall Lane.
One witness told the Yorkshire Post that some United fans were singing "You're just a town full of ISIS" to visitors from Bradford - a city with a large Muslim community - in reference to the so-called Islamic State group.
Following a review of CCTV footage and assistance from matchday stewards, the League One club have now taken action against supporters, as well as handing evidence to South Yorkshire Police and the Football Association (FA).
"Club officials have this week handed out banning orders to a number of fans and are warning that further incidents will be treated in a similar manner," a statement released by the club on Friday confirmed.
"The Blades will take every step to track down and deal with those who ignore the ground regulations and through their inappropriate language and actions cause offence and ruin the match day experience for other supporters.
"Sheffield United is an inclusive family and community orientated club where everyone is made to feel welcome and it endeavours to improve on this principle year on year."