A BRENTFORD FC match spiralled into violence after the game when a teenager was attacked by visiting Sheffield fans.
The youth, aged about 15, is understood to have been with friends when they were approached by a group of men chanting Sheffield United songs.
The boys said the men ran towards them, leaving one with a bad eye injury.
Intelligence Officer, PC Ken White, said: "It is disgraceful, the day had been really peaceful and there was a nice atmosphere and no reason for it whatsoever. We thought we had killed this sort of behaviour in Brentford and created a nice family atmosphere."
The incident is alleged to have take place in the central reservation of the A4, near a petrol station on Ealing Road at 5.45pm. Police said the suspects were white, in their early 20s and two were wearing CP jackets, thick coats with goggles attached. One was wearing a red Fila brand top.
PC White added: "It happened in broad daylight, it was so brazen. There must have been cars driving passed but no one called the police. Unfortunately the boys didn't either and it wasn't until they got to Ealing they called an ambulance, who called the police. But, of course, by the time they got there the men had long gone,
"Unfortunately there was no CCTV, and it is unlikely the boys will recognise them again, so the chances of catching these men is low."
There are ongoing enquiries between Hounslow Police, Sheffield United and South Yorkshire Police.
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