An Oklahoma student with coronavirus knowingly attended class in-person on the first day of school last week, according to Westmoore High School officials.

The student and their parents were “under the understanding that since they were asymptomatic ... they did not need to quarantine for the full 14-day-period,” officials said. The Moore Public Schools Administration conducted tracing to determine who the student may have come in contact with, administrators said in a letter to parents.

Twenty-two students who could have contacted the student, or another individual who later tested positive for the virus, are now in quarantine. The district currently mandates masks at all times for students in grades 7 through 12, and requiring them with some exceptions for younger students. “We will do absolutely everything within our power to safeguard and protect our students and our staff,” said school spokesperson Dawn Jones. “I don’t know why people do things, why they make certain decisions. What they know to be true and inform us of.”