SAN FRANCISCO (CBS SF) — Classes resumed Friday morning at Balboa High School in San Francisco a day after a gun went off inside a classroom Thursday.

Classes began at the usual start time of 8:15 a.m. School officials had announced Thursday that class would still be held the day after the frightening incident.

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There will be classroom discussions and extra counseling staff available at the school’s teen health center Friday to support students, according to the San Francisco Unified School District.

On Thursday at approximately 11:15 a.m., police responded to Balboa High School at 1000 Cayuga Ave. on a report of a gun being discharged in a classroom.

The high school immediately went on lock down, and all students were kept in classrooms behind lock doors and out of site, according to the school district.

Balboa HS classroom after reported shooting (credit: Reilly Pehling)

Nearby Leadership High School, James Denman Middle School and San Miguel Early Education School were also placed on lock down.

Responding officers searched the school and located the gun and a spent bullet casing, according to police.

Four high school students were taken into custody in connection with the incident.

SFPD on Friday confirmed that one student was booked into the Juvenile Justice Center on felony charges of assault with a firearm, carrying a concealed firearm, possession of ammunition on school grounds, minor in possession of a firearm, concealed weapon on school grounds, minor in possession of live ammunition, and negligent discharge of a firearm.

The three other involved students were released to their parents, with possible charges pending further investigation.

One student suffered injuries that were not considered life threatening during the incident, but the student’s injuries were not related to the gun discharging.

That student was evaluated and released to their parents, police said.

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The lock down was eventually lifted at all four schools, and the students at Balboa were released for the remainder of the day Thursday.

Many parents came to the school to wait for the end of the lock down to take their children home. They were stuck behind crime tape, waiting for word from school officials while their students were still sequestered inside Balboa High.

Balboa High parent Amia Taeotui doesn’t take these moments for granted. And it’s not just because she spent hours outside the school wondering about the safety of her boys who attend Balboa High.

“It’s really emotional, because we just lost one of our family members to gun violence,” Taeotui said with tears in her eyes. “And it’s so hard to be here and go through this.”

Her cousin Joe — an anti-gun violence activist — was shot and killed just two and half weeks ago.

When she found out her sons’ school was locked down because of a gun she panicked and got there as soon as she could.

Taeotui said for her and her family, the events of Thursday were still an unwelcome reminder of their loss.

“Just love them, cherish them,” she said as she cried. “Give them a big hug. It’s so emotional.”

Freshman Wallen Montes was cutting class when he was mistaken for one of the suspects during the search and briefly detained in handcuffs

“I was in the bathroom and they told me to put my hands up,” said Montes. “I thought kids were just playing with me, but I walked out and saw a gun pointed at me and they had their shields. So I dropped my phone and put my hands up.”

The students were finally allowed out when the lock down was lifted just after 1 p.m. They were clearly happy to be reunited with their parents.

“I’ll probably just go home and hug my dad for the rest of the day,” said student Thaai Lee.

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