Metropolitan Police officers were called after the document, which reportedly contained a death threat, arrived at the club's ground in west London last week.
QPR officials did not show the letter to the defender, who is at the centre of a race row involving John Terry.
A spokesman for Scotland Yard said: "I can confirm that officers are investigating an allegation of malicious communication."
The letter was delivered by hand to Loftus Road last Friday, according to reports ... so wouldn't you have thought the police would have a clue?
But ... it is Scotland Yard we are talking about.
Source: FOOTYMAD
