Police have interviewed a person under caution in connection with the alleged racist abuse of Raheem Sterling during Manchester City's defeat by Chelsea earlier this month.
TV footage appeared to show at least one Chelsea fan directing racist language towards Sterling in the match at Stamford Bridge.
A Metropolitan Police spokesman said: "Police continue to investigate an incident where is it is claimed racial abuse was directed at a player during the Chelsea v Manchester City game at Stamford Bridge on Saturday, 8 December.
"Officers are reviewing footage and CCTV to determine whether any offences have been committed.
"Officers are in possession of the details of those reportedly involved – there have been no arrests at this time. One person has been interviewed under caution.
"The Met continues to work with both clubs and a number of enquiries are ongoing."
Chelsea suspended four supporters following the incident pending further investigations.
In a statement, the club said: "Chelsea finds all forms of discriminatory behaviour abhorrent and, if there is evidence of ticket-holders taking part in any racist behaviour, the club will issue severe sanctions, including bans. We will also fully support any criminal prosecutions."
One of the men was identified as Colin Wing, who told the Daily Mail he was ashamed of his behaviour but denied using racist language towards Sterling, saying he had called him 'Manc'.
ga('create', 'UA-72310761-1', 'auto', {'name': 'pacontentapi'});
ga('pacontentapi.set', 'referrer', location.origin);
ga('pacontentapi.set', 'dimension1', 'By Press Association Sport staff');
ga('pacontentapi.set', 'dimension2', '1f49f14a-1f0e-4f4d-8782-97592f7c221f');
ga('pacontentapi.set', 'dimension3', 'paservice:sport,paservice:sport:club-news,paservice:sport:football,paservice:sport:uk');
ga('pacontentapi.set', 'dimension6', 'story');
ga('pacontentapi.set', 'dimension7', 'composite');
ga('pacontentapi.set', 'dimension8', null);
ga('pacontentapi.set', 'dimension9', 'sport:football');
ga('pacontentapi.send', 'pageview', { 'location': location.href, 'page': (location.pathname + location.search + location.hash), 'title': 'Man interviewed over Sterling allegations'});