Birmingham closed one of its largest schools for a thorough safety sweep Thursday after metal detectors and other security measures failed to keep students from handling a gun in a classroom where one 17-year-old was fatally shot and another wounded in an apparent accident.

The metal detectors at the Alabama high school were not in use that day, the district’s superintendent said Thursday.

Birmingham City Schools Superintendent Lisa Herring said the school system is reviewing security measures and protocols that were in place Wednesday, when Courtlin Arrington was fatally shot in a classroom at Huffman High School.

“We have not only heightened our procedures, but we are revamping and revisiting, with an extreme amount of urgency, those protocols, not just for Huffman High School, but for every single school in Birmingham,” Herring said at a news conference Thursday.

The superintendent said Huffman has more than 43 entry points with a combination of wand and stationary metal detectors in place, but they were not in use Wednesday. She didn’t give details about why.

Herring said Arrington, a senior who had aspirations to be a nurse, was a bright student “lost to senseless gun violence.”

“She was friendly, energetic and well-liked by peers and teachers alike,” Herring said.

The shooting took place as class was dismissing for the day, killing Arrington and injuring another student. Police said Wednesday that it was possible the shooting was accidental, but they were reviewing video footage and interviewing witnesses to determine exactly what happened.

Police took a “person of interest” in the shooting into custody Thursday but did not identify the person because no formal charges have been filed.

“Charges are pending a review of the case by the Jefferson County District Attorney’s Office,” the police statement read.

Birmingham interim police Chief Orlando Wilson said Wednesday that investigators were reviewing the possibility that the firearm had accidentally discharged.

“We have a lot of unanswered questions,” Wilson said.

Huffman High School was closed Thursday. Security was being increased at all city schools. Just last week, as police and school officials investigated a reported threat at Huffman Middle School, a gun was found outside an entrance door, believed to have been left there as students prepared to be scanned and have their backpacks checked.

Gov. Kay Ivey said she’s “praying for the family of this young lady who has tragically lost her life way too early. … It reaffirms that there is no place for students to have firearms or other weapons on campus.”

The shooting happened the day after Ivey created a school safety council to make recommendations on security in Alabama’s schools, including updated threat plans and training for students and staff on emergency situations.

A state senator became emotional on the Alabama Senate floor Thursday as she discussed the shooting, which happened in the district she represents.

“I can’t imagine a parent sending their child to school and that child never coming home. I can’t imagine what those children have gone through, not just in Huffman High School but all over this state,” state Sen. Linda Coleman-Madison said.

Alabama lawmakers have proposed multiple measures in response to last month’s killings of 17 people at a Florida high school. Republicans would arm either teachers or volunteer security forces in schools. Democrats would limit or ban the sale of assault weapons. All these proposals face a tight deadline before the end of Alabama’s legislative session this election year.

(AP)