The Football Association have begun an investigation into allegations of anti-Semitic abuse by West Ham fans during Sunday's Premier League match against Tottenham at White Hart Lane.
The announcement comes after West Ham promised strong action, saying fans will be banned from Upton Park for life if they are proven to have made the alleged chants during yesterday’s game.
The FA said in a statement: "The FA can confirm it has begun investigating reports of abusive chanting at the Tottenham versus West Ham United fixture.
"The FA governance department has this morning contacted both clubs and will continue to make enquiries into the matter in the coming days.
"We note the statement issued by West Ham and encourage clubs to identify and ban for life any individuals involved in incidents of abusive chanting.
"There is no place for anti-Semitism or any form of discrimination in football. The FA is committed to working with the clubs, Leagues, fans groups, the police, CPS and community stakeholders to play our part in addressing this unacceptable behaviour."
West Ham are studying footage from the game after a section of the visiting supporters sang “Adolf Hitler, he’s coming for you” and hissed on several occasions, mocking the mass execution of Jews during the Second World War.
Some West Ham fans also chanted “viva Lazio” and “can we stab you every week?” in a reference to trouble in Rome last week when a group of Spurs fans were ambushed in a bar by a mob chanting anti-Semitic abuse. Spurs fan, Ashley Mills of Brentwood, sustained serious wounds after being knifed during the trouble.
The club said in a statement: “West Ham United are in contact with Tottenham Hotspur to assist them with their investigation into the conduct of a small number of supporters and alleged inappropriate chanting during yesterday’s match at White Hart Lane.
“West Ham United will take the strongest possible action against any of their supporters, including enforcing life bans from the club, that are found guilty of behaviour which is categorically not condoned by West Ham United.
“During the 46 games in the Championship last season, West Ham United had zero arrests for racism or violence, so while we are surprised to see such reports today, we will examine any available evidence of such conduct thoroughly and take the appropriate action.”
The Hammers have wasted little time in showing how seriously they are taking the incident.
Two West Ham supporters were formally cautioned by officers after singing anti-Semitic chants during the match with the pair arrested during the game and accepting police cautions, Scotland Yard said.
One of those was a Hammers season ticket holder who has since been banned.
A West Ham statement said: "One of those fans has since been identified as a season ticket holder and has, this afternoon, been sent a letter containing a banning order from the club. Any other individuals identified can expect a similar swift and robust response."
The incident has also been reported to the police by the Society of Black Lawyers.
Asked if he would take the issue to the police, Peter Herbert, the chairman of the society told Sky Sports News: "We've done so already.
"In fact we were due to meet a borough commander of the Met Police either later this week or early next week and it's one of the things that will be on our agenda.
"As far as we're concerned there has to be zero tolerance of this. If these people can be identified on camera and prosecuted then that is something we'd like to see happen."
Tottenham will be submitting video evidence as part of their report to the FA.
A club spokesman said: "We are currently compiling a full report for the Football Association and shall be submitting this with all our evidence including relevant CCTV footage."
The FA said said earlier they were “likely to investigate” but were waiting to study referee Andre Marriner’s report before deciding whether to take action. They were also expecting a report from fourth official Mark Clattenburg, who was back on duty for the first time since the FA decided he had no case to answer over allegations he made a racist remark to John Obi Mikel.
Should West Ham have evidence against any of their fans from yesterday’s match, they have promised a strong reaction, which will include life bans in the most-serious cases.
The zero-tolerance policy comes after West Ham co-chairman David Sullivan spelt out in a recent club programme the need for supporters to behave appropriately.
He wrote: “It is important that every one of us acts in a way that conveys our club in exactly the right manner — we are all ambassadors wherever we watch and support West Ham and that can shape other peoples’ opinions of our great club.”
In the immediate aftermath of the game, both managers were reluctant to comment on the issue, saying they were not aware of the chants.