Croatia coach Ante Cacic has criticised the supporters who threw flares and firecrackers on to the pitch during the 2-2 draw with Czech Republic on Friday.
The closely contested encounter had to be halted in the 86th minute after several flares rained down from the stands, with a steward behind the goal subsequently injured when a firecracker went off close to his face.
Croatia were leading 2-1 at the time and their players were seen to be appealing to their supporters to calm down as trouble began to brew.
The match resumed a few minutes later, with the Czech Republic going on to net an equaliser from the penalty spot in injury time.
"The 95% of Croatian supporters are ashamed in front of Europe," Cacic told reporters after the match.
"These are sports terrorists. This is maybe just a question about six to 10 individuals. I hope they can be identified and punished.
"I hope the Croatia FA is doing everything to prevent this, but it is impossible to avoid."
Croatia star Ivan Rakitic echoed the sentiments of his coach, saying: "We have to say sorry to UEFA, sorry to the Czech Republic and to everyone around the world who loves football.
"Most supporters support this team and are real supporters. But 10 individuals can make all these problems. It is clear that the Croatian FA and [Croatian FA president] Davor Suker are fighting against this.
"I hope Uefa can understand this."
This is the second unsavoury incident involving Croatia's fans, with the country's football association having already been fined by UEFA after crowd trouble in their opening Group D game against Turkey.