Football fans were horrified when what appeared to be a swastika appeared on the pitch during a match between Croatia and Italy.
Officials frantically tried to remove the symbol during half-time but investigators believe the symbol may have been imprinted as far ahead as 48 hours before the match in the Croatian city of Split.
Tomislav Pacak, a Croatian Football Federation (HNS) spokesman, said: “this is sabotage and a felony.
“We expect police to identify the perpetrators. This is a disgrace not just for the HNS but for the whole of Croatia.
“As far as we have learned, the symbol was imprinted into the pitch between 24 and 48 hours before the match so that it could be visible during the game.
“We apologise to all fans watching the game on television, to both teams and to our guests from Italy for the Nazi symbol.”
According to the Guardian, Italy has made an official complaint to Uefa over the incident.
The match, which ended in a 1-1 draw, already had a cloud hanging over it after fans were banned from attending. Croatian fans were serving a one-match ban for racist chanting and other offences during last month's qualifier against Norway, according to Sky News.
In 2006 a large group of Croatian football fans caused uproar when they formed a human swastika and gave Nazi salutes.