The Sheriff’s Department arrested a Grover Beach man for alleged willful cruelty to a child after a homemade firework blew up and injured the man’s son in rural Morro Bay.

According to the Sheriff’s Department, at 10:15 a.m. March 22, they got a report of a 13-year-old boy that was injured “by the discharge of powder or a flare on Canet Road, rural Morro Bay,” reads the news release.

The victim had already been transported to the hospital for treatment before deputies arrived. Responding deputies called in detectives and the bomb squad to investigate.

They determined that, “the victim was injured by an illegal, homemade pyrotechnic device constructed with the consent and assistance of his father.”

The boy’s father, identified as Trevor Harris, 48 of Grover Beach was arrested on suspicion of willful cruelty to a child and for making an illegal explosive device. Deputies continue to investigate the incident.