Police are investigating claims of racist abuse against a Newcastle United player during the team's Premier League derby clash with Sunderland.
The alleged abuse was aimed at Senegalese striker Demba Ba by a Sunderland fan, according to a witness who told Sky Tyne and Wear about the remark.
It could allegedly be seen in footage broadcast on Sky Sports.
Sky Tyne and Wear passed the allegation to Northumbria Police.
A police spokesman said: "There was one report of racist language having been used by a supporter in one area of the stadium - enquiries into this report are ongoing."
Sunderland fans were also heard singing that they wished Newcastle defender Steven Taylor was dead during the 1-1 draw at the Stadium of Light on Sunday.
Taylor had been outspoken in the build-up about the rivalry between the two clubs.
Fifteen arrests were made in connection to the match, with six of them coming in a pre-planned police operation in the early morning before kick-off.
However, police said there were "very few" problems inside the stadium and praised the majority of spectators for their behaviour.
The racism allegation came amid an increasing focus on the issue in the Premier League after the FA found Chelsea and England defender John Terry guilty of using a racial remark against QPR's Anton Ferdinand.
Over the weekend, a number of players, including Ferdinand, refused to wear Kick It Out anti-racism t-shirts in protest at perceived weaknesses in punishing offenders.