Netherlands — Dutch club FC Den Bosch pledged Wednesday to do all it can to identify and punish a group of fans who hurled racist abuse at U.S. striker Jozy Altidore (pictured) during a match.

Den Bosch said fans responsible for the monkey chants Tuesday in the Dutch Cup match against Altidore’s AZ Alkmaar “do not belong in the De Vliert (Stadium) and will face the toughest possible sanctions.”

The racist chants gave a hollow ring to the slogan “without respect, no football” that was coined by Dutch soccer authorities in the aftermath of the death of a linesman who was attacked by players after a match between two youth teams near Amsterdam in December.

Altidore, who is Black, was not available for comment Wednesday. He’s played for the U.S. national team and the New York Red Bulls from 2006-08.

After the match, he told Dutch television the chants were the worst abuse he has been subjected to on a soccer field.

“It’s a bit disappointing that these things still happen in this time that we’re in,” Altidore told Eredivisie Live. “But what you going to do? You just hope these people can find a way to improve themselves. You can only pray for them.”