This month's Dutch Cup final is proving a severe headache for the Rotterdam city council. The match - a classic clash between arch rivals Ajax FC of Amsterdam and Rotterdam's Feyenoord FC - will be staged in the latter city on 25 April.

Fears of large-scale hooliganism have been prompted by campaigns on the websites of hardcore Ajax fans, who are threatening "to flatten Rotterdam again". The port city was bombed by the Germans in 1940, and a chilling picture of the flattened city centre has been posted to illustrate the threat. Calls to go rioting have also been posted on Feyenoord fansites.

Not on the list
It's not just the Ajax fans that are causing concern. Feyenoord's fans also include a group of hooligans who were involved in a mass fight with police at a beach party last year. Police fired shots which killed one of the rioters on the Hook of Holland beach, near Rotterdam, in August 2009. Some hooligans convicted for their part in the beach riot have already completed their sentences and are expected to attend the match.

As a part of their punishments, the judge banned them - by way of a precaution - from attending certain  public events, but the national football cup final was omitted from the list. Rotterdam council has now asked Mayor Ahmed Aboutaleb to extend the ban so the hooligan group can be kept away from the Ajax - Feyenoord match. The mayor has said he will announce measures on Thursday.

Returned tickets
Ajax has voluntarily limited the number of tickets sold to its supporters in order to keep the crowds manageable. Instead of 10,000 Ajax fans, 7,700 will travel to Rotterdam. The other 2,300 tickets have been handed back to the national football association, KNVB. They will be sold to fill the neutral section of the terraces, and ticket holders will only be allowed into the Feyenoord stadium when they show their ID.

Yet some Rotterdam councillors are worried that the tickets might end up in the wrong hands, namely those of Ajax hooligans.

The two sides have a long history of violent confrontations. In 1997 Rotterdam and Amsterdam hooligans fought a pitched battle on farmland outside the town of Beverwijk, west of the Dutch capital. A 35-year-old Ajax supporter was killed in the fight. In the end no one was convicted for the killing, but to this day, the incident has cast a bleak shadow over Ajax-Feyenoord duels.

(c) Radio Netherlands Worldwide