Utrecht mayor Sharon Dijkstra is seeking compensation from Portuguese football club Porto or its fans after eight buses were damaged ahead of the Europa League game against Utrecht last Thursday, she said in a letter to the council.

The buses were vandalised while fans were being transported to the Galgenwaard stadium. In total, some 78 people were arrested on the day, most of them Porto supporters.

Some 400 officers, including military police, were brought in to police the game after the local authorities were warned about riotous behaviour by Porto fans.

During preventive searches ahead of the game, police discovered illegal heavy fireworks at the home of one Utrecht supporter and in the car of a Porto supporter.

Martijn Kroef, owner of bus rental company Pouw, said supporters started to demolish the buses shortly after boarding, breaking windows and damaging air conditioning installations and chairs.

“The buses are hooligan-proof but nothing can withstand this kind of violence. The drivers felt incredibly intimidated,” he told local broadcaster RTV Utrecht.

In total, the supporters caused some €80,000 to €100,000 worth of damage to the buses, he said.

Although there were no confrontations between fans and the police, “it is regrettable that a European home game impacts the entire city and demands such a big police presence,” Dijksma said.

Utrecht will be playing English club Nottingham Forest at home on December 11 and Dijkstra will be discussing measures to ensure the safety around the stadium with police, the club and the public prosecution office.