Croatia fans who caused trouble during their team's Euro 2016 match against the Czech Republic on Friday were "sports terrorists" and had no place in football stadiums, the Balkan nation's coach told a news conference.
The supporters threw flares on to the pitch and fought among themselves in one section of the Stade Geoffroy Guichard, forcing the Group D game to be interrupted for several minutes while officials and players appealed for calm.
"We were exposed to the terror of hooligans who have no place in sports arenas and I sincerely hope they will be identified and brought to justice," said Cacic.
"They are terrorists, sports terrorists, a specific group. Unfortunately, they still exist and even enjoy some kind of support at home.
UEFA said disciplinary proceedings would be opened on Saturday once they had received official reports from the match delegate and referee Mark Clattenburg.
Cacic blamed the Croatian government for being too lenient with soccer-related offenders and not doing enough to crush hooliganism, which has been rife in the former Yugoslav republic over the last decade.
"What hurts me is that the (Croatian) authorities will not deal with the problem," he said.
"The government has not done enough to eradicate them while the Croatian Football Association just doesn't have the repressive tools to do it on its own.
"This is just a handful of thugs, maybe a dozen, but many Croatian patriots, including the players who wear the shirt with so much pride and passion, are now ashamed in front of the whole of Europe."
A small section of Croatian supporters threw eight small flares on to the pitch and attacked a much larger group who had behaved impeccably up to the point when the violence broke out.
Play was suspended as the Croatia players appealed for calm in the closing stages of the match when they were 2-1 ahead.
The Czechs, who had pulled a goal back after falling 2-0 behind, grabbed a last-gasp equaliser and Cacic was in no doubt that the trouble had deprived his distracted team of victory.
"We suffered a complete meltdown on the pitch because of a handful of irresponsible individuals and if the game had gone on for any longer, we might have lost it," he said.
The Croatians, who would have reached the last 16 with a match to spare with a win over the Czechs, play holders Spain in Bordeaux in their final Group D match on Tuesday.
