According to the Leiria Prosecutor's Office, the investigation into the accident involving the student, who died at the Leiria Hospital Centre, is being led by the Leiria Public Prosecutor's Department of Investigation and Prosecution, with the assistance of the Leiria police.
The prosecutor said the enquiry aims to investigate "the possible practice of a crime of negligent homicide".
A 15-year-old child died on 25 May after being hit by a goalpost at the Conciliar Maria Imaculada College (CCMI), in Cruz d'Areia, Leiria.
According to a source from the Leiria Hospital Centre, the child had already arrived at the emergency department of Santo André Hospital, in Leiria, where he was declared dead.
In a statement, the CCMI said that "it is with deep regret that the Conciliar School of Mary Immaculate, in Leiria, announces the death of a student from this institution, 15 years, attending the 9th year, following an accident occurred in circumstances yet to be determined.
The Cruz d'Areia school reveals that the "accident was communicated to the educational authorities, and the circumstances of what happened are being investigated through a process of enquiry".
"The director of the school is perplexed, shocked and deeply saddened by what happened, something that never occurred in school, throughout its 79 years, having provided psychological support to the family, colleagues and school community", reads the same note, where the educational institution presents the "condolences to the family and the school community".