A 17-year-old student fired shots Thursday morning at his high school in the state of Iowa, killing a fellow student and injuring four other students and an employee, according to authorities in the Midwestern U.S. state.

Mitch Mortvedt, assistant chief of criminal investigations in Iowa, said during a press conference that the victim was a sixth-grade student, meaning he was between 11 and 12 years old, and thus was not a student at this high school but was most likely there for a breakfast program.

He also added that the five injured were four students and one employee at the high school, and all of their lives are not in danger.

Mortvedt explained that the shooter is a high school student named Dylan Butler (17 years old), who was armed with a handgun and a hunting rifle, and was found "with a wound self-inflicted," a phrase usually used by authorities to describe suicide cases, but he did not confirm immediately whether he died or not.

According to the security official, security forces at the school found a homemade explosive device that they dismantled.

The shooting took place at Perry High School around 7:30 a.m., before classes started.

A large number of police cars, ambulances, and security forces immediately rushed to the shooting site.

Perry is a small town about 60 kilometers from Des Moines, the state capital.

According to Mortvedt, "Butler also posted a number of posts on social media shortly before the shooting," without specifying their content.

According to the CNN news network, Thursday was supposed to be the first day of school in this new semester, but the school announced that classes would be canceled on Friday.