David Gold has warned West Ham fans that any kind of discriminatory behaviour will not be accepted after sections of the Hammers' support sung inflammatory chants at Tottenham on Sunday.
The co-chairman has spoken out after two fans were arrested after making anti-Semitic jibes at White Hart Lane, while one fan has been given a lifetime ban from all matches for his actions.
Gold insisted that an internal investigation was underway, but was quick to back the majority of West Ham fans.
The 76-year-old told the BBC: "We have a clear stance towards any kind of discriminatory behaviour - it will not be tolerated.
"David [Sullivan] and I are leading an investigation from the top of the club to establish exactly what happened at White Hart Lane on Sunday.
"At the same time we must remember that West Ham United has some of the best fans in the land and we must not let the tens of thousands of supporters that follow our club over land and sea in exactly the tight way be overlooked."
Reports suggested West Ham fans also antagonised the home crowd about the stabbing of Spurs fans before their Europa league clash with Lazio last week.
Gold added: "Like many of the people around me in the directors' box at White Hart Lane I didn't hear or see any of the reported inappropriate behavior during Sunday's game with Tottenham.
"If I had I'm sure I would have been mortified."