Ljubljana - The Equal Opportunities Ombudsman has appealed for tolerance in the wake of a paint balloon attack on a fresco of Ljubljana's St Nicholas Cathedral, warning the act could count as discrimination.

"The buildings in which people perform religious rituals mean a lot to those people. Graffitiing or other forms of damaging of parts of those buildings could thus be understood by the believers as an attack on their right to belief and them personally," reads a release from the ombudsman's office.

The office notes that religious belief is a personal circumstance under the protection against discrimination act, which means no one should be subjected to discrimination because of their belief.

Harassment is a form of discrimination which the ombudsman understands as any unwanted conduct whose effect or intention is to create a frightening, hateful, humiliating or offensive environment for a person or insult the person's dignity.

"The effect of a certain act can thus be discrimination even when someone did not intend to harass," reads the release form office of Equal Opportunities Ombudsman Miha Lobnik.

One of the frescoes on the exterior of the Ljubljana cathedral was damaged on Monday as unknown perpetrators attacked it with a balloon filled with paint, causing several thousand euro in damage.

The Slovenian Bishops' Conference condemned what it described as an act of vandalism and Christianophobia.

The incident is being handled by police as suspected criminal act of damaging of a cultural monument.

On Saturday, a can containing unidentified flammable substance was blasted in the vicinity of a Catholic pastoral centre in the Ljubljana-Rudnik parish.