A song sheet displaying lyrics to a homophobic chant about John Terry were reportedly handed out prior to Wednesday night's EFL Cup match between West Ham United and Chelsea at the London Stadium.
The two London rivals went head to head for a place in the quarter-finals of the competition, and the Hammers came out on top in a 2-1 victory.
On social media, it has been alleged that pieces of paper were distributed encouraging West Ham fans to sing a homophobic chant about Terry just before kickoff.
A spokesman from the Metropolitan Police said: "Police are aware of a leaflet handed out before the match containing homophobic contents. This will form part of the post match investigation."
The news comes on the same day that BBC Radio 5 live found in a survey of 4,000 football fans that eight percent would stop supporting their club if a player was openly gay.
