A prosecutor in Halkida, Evia, is investigating the circumstances that led to the injury of a 13-year-old boy at a fairground in Eretria, on the Gulf of Evia.
The boy injured his leg after it became caught in a hole in a trampoline, local media reported. He is still receiving treatment at an Athens hospital.
The 55-year-old owner of the fairground, which had a license, has been arrested and charged with causing bodily harm through negligence.
Authorities have been cracking down on fairgrounds following the death in April of a boy, also 13, at a facility in southern Athens. He died when an inflatable water roller was swept away by a strong gust of wind.