An explosion in a fuel tank occurred at noon at the primary school in Serres, as a result of which two children were slightly injured and another one was found unconscious in the area.
The explosion occurred for reasons unknown so far in the 9 Serres Primary School.
A mobile EMS unit and an ambulance immediately arrived at the scene and picked up the two slightly injured children and they were taken to the city's general hospital.
The child who was found unconscious remains at the scene for now. The police have cordoned off the area.