A video in which football fans can be heard singing anti-Semitic insults is being investigated by police.
Supporters heading towards the Etihad Stadium ahead of Manchester City's Premier League game against Tottenham on Saturday were heard chanting the abuse on a tram.
The chants were apparently directed at Spurs supporters.
Police said it was treating the chanting, footage of which has been widely shared online, as a hate crime.
Among the chants, a group of men are heard singing about gas chambers in a reference to the Holocaust.
Supt Steve Howard said: "Greater Manchester Police have been made aware of a video showing people chanting anti-Semitic songs.