SANTA ROSA, Calif. >> Detectives today were investigating what prompted a fight between three students at a Northern California high school that ended in one fatally stabbing another as more than two dozen classmates watched.

A 15-year-old freshman was booked on suspicion of homicide and other charges in connection with Wednesday’s fatal stabbing in an art classroom at Montgomery High School in Santa Rosa, California. One 16-year-old junior was killed and another injured, police said.

The attack shocked Santa Rosa — a community best known for its wineries about 50 miles (80.5 kilometers) north of San Francisco — and prompted lockdowns of several nearby schools as officers searched for the teenage suspect.

The school will be closed for the rest of the week. Principal Adam Paulson, in a message to parents, students and the school community, called the stabbing “the darkest day anyone can remember at Montgomery High,” according to the Press-Democrat.

The deceased victim was identified as Jayden Jess Pienta, 16, according to Santa Rosa police. He was a junior. The victim who survived the stabbing is also a 16-year-old junior.

Jayden’s grandmother, Cheryl Griffith, told reporters that her daughter was struggling with his loss.

“How is she going to get through this?” Smith asked. “How do you let her bury her baby? I don’t understand.”

Santa Rosa Police Sgt. Christopher Mahurin today said investigators are working to interview the 27 students who were inside the classroom at the time, as well as the teacher and teacher’s aides.

Members of the New Vintage Church gathered this morning to pray for the school community.

Officers will be on the school’s campus Monday when it reopens, Mahurin said.

The violence started when the two juniors came into the classroom and started a fight with the freshman, police said. Teachers initially broke up the brawl but the freshman then pulled out a knife and allegedly stabbed the juniors.

Mahurin said detectives have not yet discovered why the upperclassmen began the brawl, though the three students appear to have known each other and had fought previously.

Santa Rosa police have not released the name of the 15-year-old student, a freshman, because he is a juvenile. He was booked on felony charges of homicide, attempted homicide and having a weapon on a school campus. He was additionally booked on a misdemeanor charge of battery on a school campus.

The teenager was taken into custody Wednesday hiding in a creek bed after he fled the classroom. It was not immediately clear whether he had an attorney who could speak on his behalf.

The Sonoma County District Attorney’s Office did not immediately have a comment today about the potential filing of charges.

“This is truly a sad day. The tragedy that happened here today is heartbreaking,” Anna Trunnell, the Santa Rosa City Schools superintendent, said at a news conference.

Several students raised questions at the news conference about their safety and asked why school officials did not do more to stop the students’ behavior despite knowing there were problems between the three teens. The officials walked out instead of answering.

Officials had earlier said none of the campuses in the Santa Rosa City Schools District have metal detectors or police officers inside.

There were no mentions of the violence on the district’s website or social media accounts this morning. A Facebook page for Montgomery High School appeared to have been taken down.

Paulson, the high school’s principal, and Santa Rosa City School District spokeswoman Vanessa Wedderburn didn’t answer voice and email messages seeking comment today.

With more than 1,600 students, Montgomery High School is the second largest school in Santa Rosa and in need of major repairs, according to a report published by The Press-Democrat last week.

The school built in 1958 has exposed wires hanging from the rafters in hallways, wooden skirting around the foundation of old portable classrooms is rotting and students often must wait to get home to go to the bathroom because the ones at the school are foul smelling and there aren’t enough available, according to students who spoke to the newspaper.

Lisa Cavin, associate superintendent of business services for the Santa Rosa City Schools district, told the newspaper the district hasn’t had the funds for some projects over the years and that constant vandalism diverts money.