The Football Association has launched an investigation into alleged racist and antisemitic chanting by West Ham United fans.
Hissing noises – intended to imitate the sound of the gas chambers – were heard at White Hart Lane during the Hammers’ game with Tottenham on Sunday.
West Ham said it would issue life bans to supporters found to have been involved in the chanting, which followed a series of apparently antisemitic attacks on Spurs’ fans in Italy last week.
Two Italians were charged with attempted murder after Spurs supporters were stabbed during an attack in Rome ahead of the club’s game with Lazio in the Europa League.
It was reported that West Ham fans at the derby match in London had chanted “can we stab you every week” and “Hitler’s coming to get you”, as well as songs in support of Lazio.
An FA spokesman said: "The FA governance department has this morning contacted both clubs and will continue to make enquiries into the matter in the coming days.
"There is no place for antisemitism or any form of discrimination in football. The FA is committed to working with the clubsl Leagues, fans groups, the police, CPS and community stakeholders to play our part in addressing this unacceptable behaviour."
In a statement, West Ham said it would assist Tottenham in its investigation to identify those responsible for the chants.
“West Ham United will take the strongest possible action against those 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 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.”
A Tottenham 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 Board of Deputies said it "utterly condemns" the chants and plans to write to the FA to raise its concerns about antisemitism in football.
A Board spokesman said: "Antisemitism has no place in football or society in general. For football fans to use Holocaust imagery and chants glorifying Adolf Hitler is grossly offensive to the Jewish community and is a stain upon the character of British football."
The Community Security Trust confirmed it had received complaints about the chants from Jewish fans who had attended Sunday's match. Spokesman Mark Gardner said CST would ask for meetings with both clubs and the Metropolitan Police to discuss the issue.
Mr Gardner said: "The days of English football crowds making massed monkey noises are thankfully gone, but massed antisemitic chanting about Hitler and gassing was clearly heard yesterday from a loud section of West Ham fans. We have heard such abuse against Spurs before and it risks seriously compromising the work against racism at all levels of the game."
The Board also highlighted an incident following Scunthorpe United's 4-0 defeat at Doncaster Rovers on Saturday. In a post-match interview on BBC Radio Humberside, Scunthorpe manager Brian Laws described his side's defending as having been "as bad as the Holocaust".
Mr Laws apologised on Monday, saying in a statement: "The use of the word was not intended to cause offence and was used in the heat of the moment, in the frustration of the defeat.
"It was a poor choice of language to define those emotions and wasn't meant in the true meaning of the word."
Radio Humberside presenters had immediately apologised on air following Mr Laws's comments.
The Board spokesman said: "Clearly there is either a lack of understanding or a lack of compassion within some sections of the British football world about these issues; a lack of understanding or compassion which needs to be addressed."