The Telegraph reports that the supporter was carted off by police at half time, following repeated warnings from the authorities that use of the word, or its derivatives, could be punishable by criminal action.
Spurs fans have continuously referred to themselves as "Yids" or "Yiddos" for several seasons, referring to their large Jewish fanbase, partly in regard to coming under torrents of abuse from rival fans at times. As per the Telegraph report:
Hundreds of Tottenham Hotspur fans had defied those warnings, however, and loudly chanted “Yiddos”, “Jermain Defoe, he’s a Yiddo” and “We’ll sing what we want” throughout the match. The [arrested] supporter, who was in the stadium’s East Stand, was held on suspicion of committing a section-five public order offence. Police are continuing to review footage of the match and it remains possible that further arrests will be made.
The subsequent arrest of the supporter during this game is thought to be the first such incident, with no punishment being meted out for those in previous matches and seasons chanting the same phrases.
Prime Minister David Cameron had previously stated that Spurs fans should not be punished for any such chanting, even while other rival fans should, because calling themselves the names would not be "motivated by hate," as per Metro.
The West Ham supporters were not directly accused or heard to sing the word "Yid" at Spurs fans, though other unpalatable insinuations were made including a brief rendition of "We won’t say his name, he’s coming for you." This is thought to be a thinly veiled reference to last season's chant of "Hitler’s coming for you"—another anti-Semitic chant which the Spurs fans have had to endure.
In the match itself, Spurs were beaten 3-0 by West Ham United, with all the goals scored in the second half from Winston Reid, Ricardo Vaz Te and Ravel Morrison. The result left Tottenham in sixth place in the Premier League table after their second defeat of the season, while West Ham's first away win of the season moved them up to 13th.