"There were no weapons on campus and students were never in any danger."
Sanzo said that students were placed "on a hold" and "remained in their classrooms" while medical officials arrived at the school and transported Halane to the hospital.
"Students were unaware of the medical emergency, which occurred in a portion of the campus that was not directly accessible to students," she added.
The students then continued on a "slightly modified schedule" and "were unaware of the medical response".
Sanzo said classes were still dismissed at the end of the day as usual to "ensure all students had safe transportation and supervision available".
"Our focus is always on the safety and well-being of our students. We felt that you should be aware of the situation in case your child comes home with questions or concerns," she added.
Crisis counseling teams are being made available to the school's campus throughout the week as needed.
Halane, who tied the knot in December 2016, was a Fine Arts teacher at the school and a piano and voice instructor.
He called himself a "lifelong music lover" who was "passionate about education and the arts".
"To me, music is like a box," he wrote in his teacher profile. "You get out of it what you put into it".
"I love giving my students the tools they need to succeed musically, and build off of the natural talent they have."
Where to get help:
• Lifeline: 0800 543 354 (available 24/7) • Suicide Crisis Helpline: 0508 828 865 (0508 TAUTOKO) (available 24/7) • Youthline: 0800 376 633 • Kidsline: 0800 543 754 (available 24/7) • Whatsup: 0800 942 8787 (1pm to 11pm) • Depression helpline: 0800 111 757 (available 24/7) • Rainbow Youth: (09) 376 4155 • Samaritans 0800 726 666 • If it is an emergency and you feel like you or someone else is at risk, call 111.