Amnesty International has said that Egypt "must immediately and unconditionally" release the 21 female protesters who were given jail sentences of 11 years each by an Alexandrian court this week.
The seven protesters who are legally minors -- ranging in age from 15 to 17 -- will carry out their sentences at a juvenile detention centre until they reach 18, then be transferred to adult facilities.
“These harsh prison sentences against young women and girls come after the adoption of a draconian protest law and the violent dispersal of an activists’ protest in Cairo," said Hassiba Hadj Sahraoui, the rights group's deputy director for the Middle East and North Africa in a Thursday statement.
"It is a strong signal that there will be no limit to the authorities’ efforts to crush opposition and that no one is immune to their iron fist."
The new protest law, which was issued on Sunday, requires protest organisers to notify authorities three days in advance of a demonstration's location, and imposes jail terms and fines on individuals who break the law.
The 21 women and girls, who were arrested at a protest in Alexandria in support of ousted president Mohamed Morsi in October, were convicted of destruction of private property, attacking security forces and inciting violence.