Police confirmed receiving a complaint on Monday that the Catholic shrine at the popular hiking spot had been desecrated by unknown perpetrators, adding that they were still looking into the matter.
The act has drawn condemnation from the Catholic Church and well as the Islamic Community in Slovenia, the larger of the two organisations representing the Muslim community in the country.
The Islamic Community's release said such acts of vandalism were unacceptable, so the community expected the police to trace down the perpetrators and respond appropriately.
The Slovenian Bishops' Conference joined the call, saying they understood the act as being directed against peaceful coexistence between religious communities in Slovenia.
The bishops expressed concern over acts of religious intolerance and desecration of religious buildings in the country, urging the authorities, media and NGOs to advocate respectful attitude to religious communities, believers and their buildings.
The incident follows several acts of vandalism directed against religious monuments last year.
At the beginning of the year, pigs' heads were left twice at the construction site of the Ljubljana mosque.
In June, the Celje cathedral was defaced with insulting graffiti and in November a precious Madonna statute was smashed with a hammer at the Koper cathedral.
The latest incident was also decried by National Assembly Speaker Milan Brglez, who described it as "outrageous act of intolerance against believers".
"There should be no place for any kind of intolerance in Slovenia," Brglez said, urging all citizens to build the country's future on what unites them and regardless of differences in their world views.