Croatian football officials on Saturday apologised for a swastika visible on the pitch during their 1-1 draw with Italy in a Euro 2016 qualifier, dubbing the incident an "obvious act of sabotage" that was reported to the police.
UEFA had ordered Friday's match to be played behind closed doors, in a virtually empty stadium, as punishment for fan violence and racist incidents when Croatia played Norway earlier in the qualifying campaign.
A swastika, however, was clearly seen on the pitch at the Poljud Stadium, the home of Croatian top flight side Hajduk Split.
It was not clear if the Nazi symbol was mowed into the grass or painted, but ground crew struggled to cover it up during halftime.
"We apologise to all viewers, our guests from Italy and the players from both teams, for the nazi symbol on the Poljud Stadium grass," Croatian federation press officer Tomislav Pacak said in a statement.
"Technically speaking, a chemical agent was used on the field 24 to 48 hours before the kick-off, timed to be visible during the qualifying match. At half-time, we tried to remedy the situation to the best of our abilities, given the short amount of time.
"We immediately notified UEFA of the incident."
Pacak added: "This was an obvious act of sabotage and a criminal act. We condemn it and ask the police and judicial bodies to find the person(s) responsible for what is a shame not only for Croatian football, but the entire country."
A UEFA spokesman told AFP that i was awaiting the reports of the referee and the body's match delegate before deciding whether to open an investigation.