Topless Internet photos of Jelena Miksa, a clerk at the culture ministry, and her relative Viktorija have been a hit on social networks and local media as they celebrated Croatia's 3-1 victory over Ireland on Sunday in Poznan, Poland.
"We have to react as a public sector employee should behave in line with the code," ministry spokeswoman Natasa Petrinjak reported to AFP.
The ministry says Miksa has been told she should ''take care of her behavior in the future.'' It said there will be no sanctions, for now.
''The wild'' women, as they have become known in Croatia, said they did it in support of the team.
After Croatia's 3-1 victory over the Republic of Ireland, the women celebrated by pulling their shirts over their breasts.
"I don't regret anything ... For me the only important thing is how my squad played. Let's go on to win," Jelena Miksa told the Vecernji List daily.
Croatia plays Italy next on Thursday before taking on defending European champions Spain on June 18 in Gdansk.