Two men have been arrested and the Football Association have launched an investigation after objects were thrown at Chelsea defender Antonio Rudiger during Sunday's 2-0 win over Tottenham at Stamford Bridge.
The incident occurred in the 73rd minute when play was suspended after it appeared a lighter among other items were aimed at Rudiger from the section containing Spurs supporters, prompting captain Cesar Azpilicueta to shout in the direction of the travelling contingent.
Referee Paul Tierney and fourth official Andrew Madley were made aware of the situation and a request followed for more stewards to be deployed to the away end.
"Two men have been arrested on suspicion of throwing objects from the stands during the Chelsea versus Tottenham Hotspur match at Stamford Bridge," a spokesperson for the Metropolitan Police said.
"They have been taken into custody. Inquiries, in conjunction with Chelsea FC and Tottenham Hotspur FC, are ongoing to identify anyone else involved in throwing objects during the match."
The FA are liaising with the Met Police and a spokesperson said: "We are investigating the incident and we are liaising with the club and the police as a matter of urgency."
When the two sides met in the Carabao Cup semifinal, first leg clash at the same venue earlier this month, Spurs subsequently released a statement condemning homophobic chanting from their own supporters during the match.
This latest incident came at the end of a week in which Aston Villa players were hit by plastic bottles thrown by Everton fans during a match at Goodison Park, and Arsenal issued a statement which warned supporters they face a three-year ban from Emirates Stadium for entering the pitch after recent matches were marred by individuals encroaching onto the pitch.
Chelsea boss Thomas Tuchel recorded a video message last week urging Chelsea fans to behave themselves and after Sunday's game, he said: "I sent a message to our supporters that we love to have them close to the pitch, that it is a brilliant atmosphere that they are not behind fences or nets.
"Everybody needs to show respect and behave to certain guidelines, there is no doubt about it.
"If this is the new trend we should act together so that it stops as soon as possible to protect the atmosphere and the environment of this game, because it is absolutely unique here in England."