The education bureau on Friday sent a letter to schools urging them to tell parents and students that the anti-mask law will be enforced from midnight.

Letter said students, teachers and staff should be told that they shouldn’t wear masks or cover their faces inside or outside campus.

It said “as a matter of principle, students inside or outside of schools should not be wearing masks”.

But it noted the new law, invoked under an emergency ordinance, exempts the ban on wearing face masks under certain conditions, like illness and religious reasons.

The letter also urged parents to remind their children not to wear masks when they go out and stressed that schools are not the place to express political views.

A student of Kwun Tong district secondary school, who gave her name as Kasey, said her school principal made a speech which was broadcast to all classes explaining the new law and asking them to uphold the Basic Law.

She said many of the students reacted furiously, with some using expletives while some pupils broke down.

Kasey said she agreed with the school’s stance about caring about students’ safety. However, she objected to the principal’s speech on obeying the law, saying the new law is an injustice in itself.

The school cancelled all extra curricular activities and extra classes for the day and requested students to leave the school after classes, saying the premises will be shut by 4:30pm.