DETROIT, MI — (CNN) The handgun was under a pillow in her grandmother’s Detroit bedroom when the five-year-old girl came upon it, police said Wednesday.

The girl, who was with two younger children, was playing with the weapon when it discharged about midnight, according to police. She was fatally wounded, the latest in a spate of shootings by children across the nation.

Her grandmother, who was cooking downstairs at the time of the shooting, was later questioned by police and released, said Detroit Police Officer Jennifer Moreno. The investigation into the tragedy continues and no charges have been
filed.

The victim, identified by CNN affiliate WXYZ as Mariah Davis, was pronounced dead on arrival at a Detroit hospital.

The other children, ages one and three, were unhurt, police said.

At least six children have shot and killed either themselves or a parent in the U.S. since April 20.

The shootings aren’t accidents, according to gun violence prevention activist Jonathan Hutson.

“These fatalities are unintentional, but they’re not accidental,” said Hutson, former spokesman for the Brady Campaign to Prevent Gun Violence. “They’re foreseeable and preventable.”

At least 14 states and the District of Columbia have laws that make gun owners criminally liable if they fail to prevent unauthorized access to guns by children, according to the Law Center to Prevent Gun Violence.

But many children are still shot unintentionally, Hutson said. On average, he said, nine children under age 18 are unintentionally shot in the United States every day. Of those, about seven die each day. Hutson said those numbers have been fairly steady over the past few years.

Twenty-four children under age 4 died from accidental shootings in 2014, the most recent year of data available, according to the Centers for Disease Control and Prevention.

The data don’t distinguish whether those children shot themselves by accident or were shot by someone else.

Hutson said responsible gun owners should keep their firearms locked in safes and store their ammunition separately when children are in the house.

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