The Football Association has launched an investigation into reports of anti-Semitic abuse by West Ham fans towards Tottenham supporters.
The chants from a section of West Ham supporters during Sunday's Barclays Premier League match against Tottenham 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. The FA governance department has this morning contacted both clubs and will continue to make enquiries into the matter in the coming days."
The statement continued: "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."
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 some Hammers supporters appeared to mock the gassing of Jews in the Holocaust during the match at White Hart Lane.
The reported abuse came four days after Spurs fan Ashley Mills was stabbed in an anti-Semitic attack before Tottenham's game in Rome. 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. West Ham insisted they will take the "strongest possible action" including life bans for any fans found guilty of anti-Semitic chants at Tottenham.
West Ham said in a statement: "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."
Police confirmed that two West Ham supporters were formally cautioned by officers after singing anti-Semitic chants during Sunday'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.