An Iranian teachers' union has called a two-day strike from Sunday over the lethal targeting of schoolchildren in a crackdown on protests sparked by Mahsa Amini's death.
The death of 22-year-old Amini, after her arrest for allegedly breaching Iran's strict dress code for women, has fuelled the biggest protests seen in the Islamic republic for years.
Young women, university students and schoolgirls have led the charge, removing their headscarves, chanting anti-government slogans and confronting the security forces on the streets.
The Co-ordinating Council of Teachers Syndicates on Thursday called a strike in response to the crackdown that Amnesty International says has cost the lives of at least 23 children.
"The Co-ordinating Council declares sit-in strikes for Sunday and Monday. We teachers will be present at schools but will refrain from being present in classes," it said in a statement posted on its Telegram channel.
"We know very well that the military and security forces and plainclothes (officers) have violated schools and educational centres," it said.
"During this systematic oppression, they have mercilessly taken the lives of a number of pupils and children; from Nika (Shahkarami) and Sarina (Esmailzadeh), to Abolfazl (Adinezadeh) and Asra Panahi."
The four, all in their teens, were killed by Iran's security forces during the crackdown on the nationwide protests that has flared since September 16, when Amini died in custody, according to human rights groups.
Oslo-based group Iran Human Rights said on Thursday that at least 27 children have been killed by the security forces and that children and teachers are among the thousands arrested in the crackdown.
In its statement, the teachers' union said "a large number of teachers have been arrested" without being charged.
"The rulers must know that ... Iran's teachers do not tolerate these atrocities and tyranny and proclaims that we are for the people, and these bullets and pellets you shoot at the people target our lives and souls," it said.
"This is why the Co-ordinating Council of Teachers Syndicates supports the rightful protests of the people across Iran, and condemns the killings and oppression of past weeks."
It vowed to "continue our protest until the people's right to protest is recognised, all pupils are unconditionally freed and return to schools, the system stops killing the people and children, and stops answering the people's rightful demands with bullets".