LAS VEGAS (AP) — A 16-year-old high school student has been jailed in Las Vegas and will be prosecuted as an adult on sex assault and attempted murder charges following an after-school attack on a teacher, authorities said Friday.

Las Vegas police said the female teacher was punched and choked into unconsciousness and the student fled the Eldorado High School campus before another school employee found the teacher and summoned police and medical help.

The woman was treated for multiple injuries, police said.

The student was arrested by school police several blocks from the campus that serves about 2,000 students several miles east of downtown Las Vegas. His name and the name of the teacher were not immediately made public.

On Friday, school administrators issued a statement to parents calling the attack “an isolated incident,” and Clark County School District Superintendent Jesus Jara sent a message to employees calling safety “our top priority.”

“I am devastated, and the CCSD family hurts for the teacher assaulted at Eldorado High School,” Jara’s message said. “Our hearts are heavy because of the violence committed against her, and we pray for her full recovery.”

But the violence was only the latest for the sprawling district, the nation’s fifth-largest with more than 300,000 students and more than 18,000 teachers at about 336 schools — including more than 70 high schools — in an area the size of New Jersey. The district began a weeklong spring break after classes were dismissed on Friday.

On Wednesday, a 17-year-old boy was arrested after a loaded gun was found on the floor of a school bathroom at a northwest Las Vegas high school.

On March 29, a campus police officer fired three gunshots at a moving car that had struck a girl amid a report of a fight in a parking lot at a downtown Las Vegas high school. Four teenage non-students were in the car. The driver and a passenger received minor wounds, and the girl struck by the car was not seriously hurt.

A day earlier, a 36-year-old mother was arrested near a Henderson high school and accused of trying to kill two schoolgirls by driving her vehicle into them to prevent them from fighting her daughter after an on-campus dispute. Police said the injured girls had broken bones but were expected to recover.

In early March, 11 people were arrested, including an adult who allegedly entered a southwest Las Vegas high school campus during several days of student fights, social media threats, classroom lockdowns and an unproved report of a gun.

In February, video posted to the internet showed a female high school student attacking a girl who was seated at a desk, pummeling her with about 35 punches to the back and side of her head.

Jara, who was abruptly fired by the school board in October and reinstated about three weeks later with no public explanation, issued a recent public plea for an end to violence. He blamed it on “the stress, anxieties and isolation of the (coronavirus) pandemic.”

Since schools began in August, campus police have reported 3,000 assaults and fights, and confiscated more than 25 guns, the school district police chief said.

“As I have said previously,” Jara said in his message on Friday, “violent acts, assaults, and bullying will not be tolerated … and those who choose to engage in these activities will be prosecuted to the fullest extent of the law.”

School police Lt. Bryan Zink said the teen arrested after Thursday’s attack was taken to the Clark County jail and would face charges as an adult.

Las Vegas police said he was booked on attempted murder, sexual assault, battery, kidnapping and robbery charges. It was not immediately clear when the teen would face a judge or if he had an attorney. The charges against him could put him in prison for the rest of his life.

Las Vegas police said in a statement that investigators determined he entered the teacher’s classroom “to talk about his grades.”

“At some point, the (student) got violent and began punching the (teacher) and strangled her until she lost consciousness,” the statement said.