A 15-year-old boy has been arrested for sending a racist tweet to Manchester United defender Rio Ferdinand in the wake of Sunday's derby encounter at the Etihad Stadium.

The authorities opened up an investigation after the tweet was sent during the match, which United won by three goals to two.

Those enquiries resulted in the arrest of an unnamed teenager, who was questioned last night by police. He has since been bailed pending further findings.

Ferdinand was also struck just below the eye by a coin thrown from the home supporters sction as he celebrated United's late winner.