Police are investigating how a gun ended up in the backpack of an 8-year-old girl at a school in St. Paul’s Payne-Phalen neighborhood.

The child was getting ready to go outside and play Monday afternoon when she placed her backpack on the floor and heard a thud, police spokesman Sgt. Mike Ernster said.

When the student opened the bag, she found a handgun inside and immediately told her teacher, Ernster said.

John A. Johnson Achievement Plus Elementary Principal Lisa Gruenewald responded immediately and secured the gun, she wrote in a letter to parents. She said the incident happened at the end of the school day.

“Nobody was threatened; nobody was injured,” Ernster said. “(The girl) told staff she didn’t know there was a gun in her backpack.”

Police were sent to the school just after 3 p.m. Monday. Officers found that the 9 mm pistol was loaded but that there was not a round in the chamber, meaning it would not have fired a bullet if someone had only pulled the trigger.

The gun belongs to the girl’s mother, Ernster said. The child told police she didn’t know how the gun got into her backpack, and she was released to her mother.

Gruenewald noted in the letter that “there are consequences for students in situations like this.”

“The safety of our students and staff is of paramount importance,” said Kevin Burns, St. Paul Public Schools spokesman. “We are taking this situation seriously, and ask our families and members of the community to help us by checking students’ backpacks and other items to help ensure schools remain as safe as possible.” Related Articles St. Paul woman sentenced for manslaughter in man’s death; murder charge dismissed

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In April, a 7-year-old boy brought his mother’s loaded handgun, which had a trigger lock on it, to Highland Park Elementary School in St. Paul. It was found in the student’s backpack and was not used to threaten anyone, police said.

The boy’s mother had reported the gun stolen a few days earlier. Police said Tuesday that case remains under investigation.