NEWCASTLE, England -- Police are investigating an allegation of racist abuse following an altercation between Manchester City defender Aleksandar Kolarov and a Newcastle supporter during a Premier League match on Saturday.

Kolarov, who is Serbian, was warming up as a substitute when he is believed to have become involved in a lengthy exchange with a fan who was carrying an Albanian flag.

Northumbria Police say they have "received a report of racist language having been used at the St James' Park stadium," adding that "enquiries are ongoing into the incident."

There is a long history of tension between Serbia and Albania, particularly over the disputed region of Kosovo.

Kolarov came on as a 37th-minute substitute in City's 3-1 win.