BALTIMORE (AP) — A Baltimore grandmother faces criminal charges for failing to secure the gun that her 9-year-old grandson was carrying when he fatally shot a teenage girl last summer, officials announced Thursday, saying the indictment should serve as a warning about the importance of safe firearm storage.

Nykayla Strawder, 15, was hanging out on the front porch of her family’s west Baltimore rowhouse with other kids when the gun discharged. Police said it was accidental.

Under Maryland law, the 9-year-old can’t face criminal charges because of his age. But the August shooting prompted outrage from the victim’s family and calls for adults to be held accountable for allowing children access to deadly weapons.

Baltimore police previously said the gun was registered to a female relative of the boy who worked as a private security guard.

A grand jury indictment now accuses his grandmother, April Gaskins, of reckless endangerment and two counts of failure to secure a firearm with an unsupervised minor present, the Baltimore State’s Attorney’s Office confirmed Thursday. Court records show the indictment was filed in November, but Gaskins, 54, was arrested this week.

Gaskins has no attorney listed in court records. Messages left at numbers listed under her name were not immediately returned Thursday.

“While I cannot discuss the details of an open and pending case, it is evident that the grand jury’s decision exemplifies how gun violence is of the utmost importance in our city,” said State’s Attorney Ivan Bates, who took office last month. “It further underscores the seriousness of responsible gun ownership and proper gun storage.”

Baltimore recently recorded over 300 annual homicides for the eighth consecutive year despite several ongoing anti-violence initiatives.

Loved ones and activists demanded “Justice for Kayla” after her death came to symbolize the myriad broken systems that have contributed to Baltimore’s high homicide rate. Family and friends remembered the high school sophomore as a vibrant personality with a bright future.

“How do you not notice your gun was missing? There is no excuse — knowing there’s a child in the home and not keeping your gun hidden,” her father, Dontay Jones, told The Baltimore Sun last year. “Our daughter is never coming back. We’ll be looking down at our daughter in a casket. I’ll never see her smile again.”

Maryland law says an adult cannot leave a loaded firearm “where the person knew or should have known that an unsupervised child would gain access” to the weapon — a misdemeanor offense whose maximum penalty is a $1,000 fine. Reckless endangerment is also a misdemeanor that carries up to five years in prison and a $5,000 fine.

“This indictment sends a strong message that we will hold accountable those who do not practice responsible gun ownership and secure their firearms,” Baltimore Police Commissioner Michael Harrison said in a statement Thursday.

Under a bill state lawmakers passed last year, children under 10 cannot be charged with a crime. Extensive research shows young children are unable to fully understand the consequences of their actions and the workings of the criminal justice system.

News of the indictment comes in the aftermath of a January shooting at a Virginia elementary school, where a first-grader brought his mother’s handgun to class and shot his teacher. Virginia law prohibits leaving a loaded gun where it is accessible to a child under 14, but no charges have been filed against the boy’s mother.

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