The Football Association has launched a swift investigation into the crowd trouble which marred the FA Cup derby between West Brom and Wolves.
Play at the Hawthorns was suspended for over half an hour due to disorder in the stands and fans spilling onto the pitch.
West Midlands Police said two people were arrested after the disturbance and another was arrested prior to the match for possession of an offensive weapon, while a man was taken to hospital with head injuries.
An FA statement read: “The disorder that occurred at the Black Country derby between West Bromwich Albion and Wolverhampton Wanderers is completely unacceptable.
“Safety and security are of the utmost importance, and the behaviour of those involved is dangerous and inexcusable.
“We will be investigating these serious incidents alongside the clubs and the relevant authorities, and the appropriate action will be taken.”
The stoppage came shortly after Matheus Cunha had struck to give Wolves a 2-0 lead in the 78th minute.
Police and security needed to rush to a corner of the ground supposedly holding home fans as the disturbance developed.
Some West Brom players were concerned for family members seated nearby and went into the stand to remove their children.
Referee Thomas Bramall eventually took the players from both teams back to the dressing rooms.
Baggies manager Carlos Corberan confirmed no players’ family members were hurt in the disturbances.
He said: “Unfortunately this happened but fortunately no dramatic situations with the families or with any person happened, because of course the lives are more important than anything.
“Everything was controlled by the security people and the situation didn’t have any negative consequence for the families. But of course the players were worried because they knew that the families were there.”
There had earlier been pockets of trouble in other parts of the ground.
Flares were thrown in the away section after Wolves opened the scoring in the first half and objects were also thrown at visiting midfielder Tommy Doyle as he prepared to take a corner.
Play eventually resumed with just over 12 minutes of the game remaining.
The Baggies issued a statement condemning “in the strongest terms the unsavoury scenes” which disrupted the game and vowing to work with West Midlands Police and the FA to investigate the matter.
“Any individual involved in the disorder will be subject to a club ban, in addition to potential criminal investigation,” the club said, before adding they would make no further comment until the conclusion of a “full and thorough investigation”.
West Midlands Police said: “We have extra officers at this local derby and they responded immediately as disorder in the stands caused fans to spill onto the pitch. Two people have been arrested for public order offences.
“We worked with officials to get the game restarted as soon as possible.
“Another man was arrested before the game for possession of an offensive weapon. A man has been taken to hospital with head injuries.”
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