(JTA) — The British Transport Police is investigating an incident in which soccer fans allegedly chanted anti-Semitic slurs while riding a London subway train.

Video filmed by another passenger and circulated on social media shows several men, believed to be supporters of the West Ham United club, chanting “I’ve got foreskin, how about you? F******Jew” while passing through the Stamford Hill neighborhood, Fox Sports reported. Stamford Hill has a large population of Hasidic Jews.

The men reportedly were en route to a soccer game on Sunday between West Ham and Tottenham Hotspur, a club with many Jewish and pro-Jewish fans.

In a letter emailed to Sunday’s ticket holders, the West Ham team wrote that it will “continue to adopt a zero tolerance policy towards any form of discriminatory behaviour and any fan found to be acting inappropriately — including racist, anti-Semitic and homophobic behaviour — will be punished to the full extent of the law and banned from attending matches.”