After the Hammers’ 1-0 win, which booked the club a place in a first major European final in 47 years, a large group of hooded AZ fans broke out of their section to attack a section of the visiting supporters. Among them were West Ham officials, former players and the families of players and staff, who were unharmed.
Dutch police are working to identify those involved and made a television appeal in the aftermath of the attack. UEFA are reviewing reports of what took place and AZ have now issued 43 stadium bans, with more possible.
The Dutch club said: “AZ has now issued 43 stadium bans in response to last week’s disturbances. It concerns visitors who were involved in the misconduct surrounding the European semi-final in Alkmaar.
“It is by no means excluded that even more local stadium bans will be imposed. Apart from this decision from the club, the criminal investigation by the authorities is still ongoing."