THREAT: Croatia supporters have allegedly singled out the referee

Supporters are believed to have planned an attack on referee Bjorn Kuipers in the 30th minute of the game, according to Croatia’s police chief.

It comes just days after fans were filmed throwing flares onto the pitch during their group game against Czech Republic.

And only today, Daily Star Online exclusively revealed how Croatian supporters are looking to "reclaim" their crown as the "first ultras" from Russian hooligans.

Nikola Kajkic, president of the Croatian Police Union, said: “We have information that the same people that caused trouble in Saint Etienne will try the same.

"And they could try to attack the referee in 30th minute of the match.

"All the information we received ahead of the Czech Republic match proved to be right.

"And, as this time, we passed all intel to French police."

Croatia were fined over £70,000 by Uefa after disturbances in the game against Czech Republic.

The Croatian Football Federation were also prohibited from selling tickets to fans identified as hooligans.

Despite the threat, thirty minutes went by without incident.