Alleged homophobic chanting by Manchester City fans during the FA Cup win over Chelsea is to be investigated by the Football Association.
It comes two days after the FA said it will speak with Manchester United after chanting of a similar nature during their 3-1 win over Everton on Friday.
Manchester City said the club "strongly condemns the behaviour of a minority of fans".
City added: "We are proud to celebrate inclusivity in football and ask all fans to join us in creating a positive environment and atmosphere, where everyone is welcomed, accepted and has a fantastic matchday experience."
The FA said: "We continue to work closely with the Crown Prosecution Service, as well as the UK Football Policing Unit.
"Part of our work in this area has been to provide the relevant authorities with impact statements from LGBTQ+ supporters, detailing how chants of this nature affects their experience and feeling of inclusion at football matches, so that a clearer stance and understanding on the chant can be established.
"We stand firmly against all forms of discrimination and are striving to ensure our game is a safe environment for all, which truly embraces diversity and challenges hateful conduct both on and off the pitch."
There also appeared to be some disturbances involving Chelsea fans late in the game, with police visibly stepping up their presence at the end where the visiting supporters were situated.
In January 2022, the Crown Prosecution Service classed the chant apparently heard on Sunday as a homophobic slur and said fans singing it during matches were committing a hate crime.
Those found to have used the words could face prosecution.
This month Nottingham Forest said they would investigate alleged homophobic chanting heard during the 1-1 league draw with Chelsea at the City Ground.