On the morning of October 31, 15-year-old Yomna Abu Eissa was wearing her school uniform and carrying her backpack when she was handcuffed and taken into custody in Alexandria, Egypt's second-biggest city .

Her school uniform was ultimately replaced by the plain white garments worn by prisoners. In November, a court sentenced Yomna to 11 years in prison for participating in a peaceful rally supporting ousted Egyptian President Mohamed Morsi.

Yomna was one of seven minors and 21 women accused and convicted of being part of a group called "7 am", for the hour at which they began their peaceful march, which opposed the military-led overthrow in July of their country's first freely elected president.

The verdict, which sparked outrage among human rights groups, offers evidence of the current government's hardline approach towards its opponents.

Although an adviser to Adly Mansour, Egypt's interim president, said he may pardon the women after a final verdict is passed, the Alexandria court responsible for handing the sentences said its ruling was justified. Arguing that the law does not distinguish between the two genders, it said recent investigations proved that the female protesters gathered with the purpose of wreaking havoc before Morsi's trial on November 4.

"The women and girls should not have been arrested in the first place, let alone detained, and sentenced to such heavy prison terms - simply for peacefully expressing their views and exercising their right to freedom of assembly," Diana El Tahawy, Egypt researcher at Amnesty International, told Al Jazeera.

According to Yomna's father, Anas Abu Eissa, she had nothing but school books in her bag and was heading to her physics class. The court, however, convicted her of possessing weapons, engaging in acts of violence and encroaching on public and private property.

"There is nothing that we can do but pray," Anas told Al Jazeera, who denied that his daughter participated in the rally. "She was heading to her class, but now her whole future is at risk. But, let's assume she did join a march. Does this justify such a cruel verdict?"

While the adult defendants were sent to jail, the seven underage girls were remanded to juvenile detention until they reach legal age. Yomna was sent to an orphanage.

She is one of many minors who have been detained since Egypt's security forces launched an intense campaign targeting the deposed president's supporters, leaving hundreds dead and placing thousands in prison cells.

"They want to terrify us. They want us to crawl into our homes and remain silent. They're intimidating the parents by arresting their children, sending a message of fear. It's a military coup - what else can we expect?" Anas said.

Anas, however, is relieved that his daughter receives good treatment at the orphanage where she stays. A day before the controversial verdict was handed down, several prominent female protesters were reportedly molested and sexually abused during an hours-long detention following a rally.

Protest law

The secular and liberal activists at the rally were not on the streets to demand Morsi's return, but were protesting against a law issued by interim President Adly Mansour mandating that protesters secure the Ministry of Interior's approval at least three days ahead of organising demonstrations. According to Prime Minister Hazem el-Beblawi, the law intends to "regulate protests" and punishes those who "break the system and threaten citizens and assault buildings".

I pray they will be released before the pardon, which can be months, or years. Pardoning them also means they are guilty, and I know they're innocent. - Ramadan Abdel Hamid, husband and father of detainees

A similar bill was proposed in 2012 by Egypt's Muslim Brotherhood-dominated parliament, but it never became law.

Beblawi's deputy Hossam Eissa has defended the controversial measure, arguing on an Egyptian talk show that the law is in fact "freer" than similar legislation in the Western world. "The law is effective," he said. "For a state to be a state, its laws have to be respected. How can a group of protesters take to the streets to defy a law, to defy the state? This is only a tool to regulate protests, and we have followed in this tool the highest standards adopted in the Western world."

Several Egyptians have already been arrested for allegedly violating the protest law, including three prominent activists who opposed Morsi's rule and played a pivotal role in spearheading the 2011 uprising against his predecessor Hosni Mubarak. Ahmed Maher, a co-founder of the April 6 movement that helped orchestrate the 2011 uprising, and Ahmed Doma were referred to trial for inciting violence and calling for protests without permission, while activist Alaa Abdel-Fattah is still being investigated for the same crimes.

"These sentences come against the backdrop of the authorities' crackdown on any dissent, including alleged supporters of the Muslim Brotherhood as well as opposition activists critical of the Muslim Brotherhood," Amnesty's El Tahawy said.

Despite the law, Egypt has seen daily protests, and at least three people have been killed since the measure was passed. "We will continue protesting. We will continue voicing our rejection to this oppressive tyrannical regime," Mohammed Kamal, a bureau member of April 6, told Al Jazeera. "This fragile, incompetent system needs to learn from previous regimes."

Until recently, protests staged since the July overthrow had been staged almost exclusively by Morsi backers. That has changed now - but although Morsi supporters and liberal activists are both demonstrating against the current government at the moment, the gap between the two groups remains wide. "We sympathise with the Alexandria women from a humane point of view, but that's separate from our political stand," said Kamal. "We won't stand on the Brotherhood's side. They're insincere in achieving reforms and the [2011] revolution's goals and are after personal gains."

'I know they're innocent'

Ramadan Abdel Hamid, whose wife and daughter are among the detainees arrested for their alleged participation in the October 31 march, says he appreciates any help that could free them. "We never were into politics. We never joined marches. We just minded our own business," he told Al Jazeera, his voice quivering.

He's worried about the safety of Rawda, his 15-year-old daughter who has been sent to juvenile detention. "The treatment is good, but she's locked up with girls arrested for prostitution and murder." With an appeal hearing for the 21 women set for December 7, Ramadan said he is trying to remain hopeful.

But the defendants' team of attorneys is not as optimistic. Lawyer Ahmed el-Ghamry, the spokesman of the team, said the ruling was "shocking and unexpected, yet the appeal's outcome is almost preconceived".

Denying the court's justifications, el-Ghamry cited cases in which prominent young people sentenced for evading military service were not punished - because, he said, "the court looked after their future and careers. Don't these teenagers deserve the same?"

The defence lawyers have faced their own legal problems. Ahmed el-Hamrawi, who heads the group of attorneys, was briefly detained on Monday on charges of inciting violence. He was released after hours of investigation.

"I pray they will be released before the pardon, which can be months, or years. Pardoning them also means they are guilty, and I know they're innocent," said Ramadan as he wept.

Follow Dahlia Kholaif on Twitter: @Dee_Kholaif