A section of West Ham fans mocked the stabbing of a Spurs fan in Rome during Tottenham's 3-1 victory over their London rivals at White Hart Lane on Sunday.
A group of away fans were heard hissing, mimicking the sound of Jews being gassed during the Second World War, and also chanted the name of Adolf Hitler.
Hammers boss Allardyce has condemned the chanting and called on the club's fans to contact the police about anything untoward they heard during the match.
"I don't view any type of chanting (of that nature) to be allowed or accepted in the game of football today," Allardyce told a press conference.
"The West Ham fans are absolutely fantastic with the support they give us and then you've got this small minority that are creating this sort of ill-feeling towards the vast majority of West Ham fans.
"I think that fans who are next to these people should deal with them first and foremost if possible."