West Midlands police have vowed to identify and punish fans involved in violence at the end of Birmingham's Carling Cup win over Aston Villa.

Nearly 500 police were on duty in and around St. Andrew's and so far they have arrested seven supporters.

But now they are concentrating on rooting out the troublemakers behind the ugly scenes inside the stadium.

More than a thousand Blues supporters invaded the pitch after their side's 2-1 win.

They confronted the 3,800 Villa fans situated in the Gil Merrick Stand at the other end of the stadium.

A flare appeared to be thrown into the section housing the Villa supporters although it was then tossed backwards and forwards between the rival factions.

Seats were also ripped out and used as missiles along with other objects.

Supt. Steve Graham told Sky Sports: "The passion we saw 80-85 minutes was exactly what we are proud of within the English game.

"It is just a shame it spilled over into the criminal behaviour we saw on the pitch at the end.

"There have been seven arrests but that was over the course of the whole operation.

"When the pitch invasion occurred, we were more concerned about asserting some control within the stadium and making sure the crowd dispersed safely and securely."

Supt. Graham added: "We've started a post match inquiry whereby we will seek to identify people who committed criminal offences.

"Sadly we've had some experience of this in the past although it is still an unusual event.

"But we will put steps in place now to identify those offenders, prosecute them and, if they are convicted, they will be banned for along time."

Supt. Graham admitted: "I wouldn't say we were expecting trouble but we knew it was a strong possibility.

"It has happened in the past, we have got intelligence, and that's why we had the level of officers on duty that we did have."

The Football Association immediately pledged to carry out a full investigation and called for any identified culprits to be banned.

An FA spokesperson said: "We wholly condemn the actions of any individuals who have been involved in the scenes of disorder at St Andrew's.

"The FA abhors acts of violent behaviour and we urge the clubs and authorities to identify any individuals involved in disorder, and impose the stiffest available sanctions, including banning orders.

"The FA will fully investigate the matter in conjunction with the appropriate authorities.

"The whole of English football has worked hard to eradicate scenes of disorder from our game.

"Home Office figures this week showed a significant drop in arrests at the many thousands of football matches held every week, the majority of which still pass trouble free."

Birmingham have also promised a full investigation in co-operation with the FA and police into the ugly scenes.

A club statement read: "Birmingham City Football Club is disappointed with scenes at St Andrew's following the Carling Cup tie against Aston Villa.

"The club does not tolerate the breaking of any stadium rules and will conduct a full investigation in conjunction with the FA and police and take appropriate action.

"A meeting will be held at St Andrew's on Thursday to investigate the matter further."

Villa also pledged full co-operation with the FA and relevant authorities.

A club statement read: "Following the scenes in the aftermath of the Carling Cup quarter-final at St Andrew's, the club will co-operate fully with the FA in its investigation in conjunction with the appropriate authorities."