A full-time member of Manchester City Football Club's groundstaff has taken to Facebook to inflame relations between the two Manchester football clubs ahead of the city derby tomorrow.

The club moved quickly to close down Ged Coyne's Facebook account after referring to Manchester United manager Sir Alex Ferguson as 'Alex purple-head Ferguscum' and describing the club as “scum” in a series of rants.

The 31-year-old admitted dedicating his public page to his antipathy towards United, but explained to club officials that it was intended as “banter”. Greater Manchester Police this week contacted both Manchester clubs to stress the importance of not inflaming tensions ahead of the game and also launched an local advertising campaign and dedicated anti-hooligan website.

The social media gaffe comes at a time when Manchester City are said to be educating all staff, including players, about the perils of broadcasting via Facebook and Twitter. The club have put together a booklet reminding staff of what is acceptable to post online.

Last month Liverpool player Ryan Babel was fined by the FA for posting a a mocked-up photograph of referee Howard Webb in a Manchester United shirt after Liverpool lost a crucial FA Cup game.