John Terry has been interviewed under caution about an alleged racist slur towards Anton Ferdinand, police sources have confirmed.
The Chelsea and England captain has denied making the alleged comments to the QPR defender during a Barclays Premier League match at Loftus Road last month.
Scotland Yard said they were looking into the incident and that a 30-year-old man was interviewed under caution on Friday.
A force spokesman added: "Police were notified of an incident on Sunday 23 October involving alleged racial abuse. This is currently being assessed by officers from Hammersmith and Fulham."
Videos of the alleged incident circulated on the internet in the aftermath of last month's game, with some claiming the footage shows Terry insulting the QPR player using racist language.
The west London derby saw Hoops striker Heidar Helguson convert an early penalty to give the home side their first win over their local rivals for 16 years.
Shortly after the allegations were made, Terry issued a statement saying: "I've seen that there's a lot of comments on the internet with regards to some video footage of me during the game.
"I'm disappointed that people have leapt to the wrong conclusions about the context of what I was seen to be saying to Anton Ferdinand. I would never say such a thing, and I'm saddened that people would think so."
A Football Association investigation into the alleged incident has been put on hold until the police investigation is completed.
Terry, 30, captained England to a 1-0 friendly win against Sweden at Wembley on November 15 and scored for Chelsea on Saturday in their 3-0 league win against Wolves.
