Announcements at the Tottenham Hotspur Stadium warned supporters to refrain from racist behaviour after Chelsea defender Antonio Rudiger was seemingly the target of abuse during Sunday's Premier League game against Spurs.
Chelsea were on their way to closing out a 2-0 win against their London rivals when, in the 63rd minute, Germany international Rudiger gestured to the officials in a manner that suggested he had been targeted by racial slurs.
The flashpoint came after objects were thrown at Chelsea players from a section of the home support.
Around 10 minutes later, an announcement on the stadium's public address system said: "Racist behaviour from spectators is interfering with the game."
A second warning followed five minutes from time, with another being issued in stoppage time.
Tottenham versus Chelsea is the second high-profile game in the Premier League to be stained by apparent instances of racism this month.
On December 7, during the closing stages of Manchester United's 2-1 derby win at the Etihad Stadium, a Manchester City fan appeared to direct a monkey gesture towards Fred and Jesse Lingard.
Greater Manchester Police arrested 41-year-old Anthony Burke on suspicion of a racially aggravated public order offence after the incident. Burke has since been released on bail pending further enquiries.