West Ham's Israeli international Yossi Benayoun tonight spoke of his disappointment and embarrassment at hearing anti-Semitic abuse by some of the club's fans towards Tottenham's supporters.
The Football Association today launched an investigation into reports of the abuse, while West Ham reacted by banning one of two fans cautioned by police at the match at White Hart Lane yesterday.
Hammers fans yesterday appeared to mock both the gassing of Jews in the Holocaust and the knife attack on a Spurs fan before Tottenham's game in Rome last week.
West Ham supporters sang "Viva Lazio", "Can we stab you every week?" and hissed on several occasions, apparently mocking the mass execution of Jews during the Second World War.
There were also reportedly chants about Adolf Hitler during the match which Spurs won 3-1.
Benayoun said on Twitter: "I have a great relationship with the West Ham United supporters, from my first spell at the club and again now I am back on loan here.
"This why I was very disappointed to hear some of the songs yesterday and it was embarrassing."
Police confirmed that two West Ham supporters were formally cautioned by officers after singing anti-Semitic chants during yesterday's match.
The pair of fans were arrested during the game and accepted the police cautions, Scotland Yard said.
One of those was a Hammers season ticket holder who has since been banned by the club.
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."
"West Ham 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."
The chants from a section of West Ham supporters have been reported to the police by the Society of Black Lawyers.
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."
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."
Peter Herbert, the chairman of the Society of Black Lawyers, confirmed his organisation had already notified police after the abuse during the match.
Asked if he would take the issue to the police, Peter Herbert 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."
The Community Security Trust (CST), a charity that monitors anti-Semitism, said it has received complaints from people in the Jewish community following the Spurs match yesterday, including from people who were at the game.
CST spokesman Mark Gardner said: "The days of English football crowds making massed monkey noises are thankfully gone, but massed anti-Semitic 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.
"UEFA and the FA need to take urgent action regarding Lazio and West Ham respectively. Fans who indulge in racist or anti-Semitic behaviour should be arrested, charged and banned. We cannot have 'the football family' ignoring, and therefore encouraging, mass Nazi chanting."