Mahmoud Mohamed Hussein was arrested when he was 18 years old on January 25, 2014, with police accusing the then-teenager of illegal protesting, getting paid to protest, possessing Molotov cocktails, and belonging to a "terrorist" organisation.
Back then, he was walking home from a peaceful demonstration to commemorate the third anniversary of the January 25 revolution.
He was detained while wearing a protest scarf and a T-shirt which read: "A nation without torture" at el-Marg checkpoint in Cairo.
Since his detention, Hussein - who turned 20 in jail on January 1 - has faced near-automatic detention renewals, more than 20 of which were decided in his absence from the courtroom.
His latest detention renewal hearing was held on January 6, 2015 - the 25th such hearing.
The two-year anniversary of his imprisonment is on Monday. He is yet to be formally charged or tried for any offence.
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Several rights groups say the student was tortured, ill-treated and forced to sign a confession during his detention.
"Under Egyptian domestic law, a person may only be held for two years prior to sentencing," Wade H McMullen Jr, managing attorney at the US-based Robert F Kennedy Human Rights group, told Al Jazeera.
"By their own law, Egyptian authorities are required to release him from detention."
The Washington DC-based group has submitted a case calling for urgent action to the United Nations Working Group on Arbitrary Detention in conjunction with the Association for Freedom of Thought and Expression, an Egyptian nongovernmental organisation, and Malek Adly, an Egyptian human rights lawyer.
Asked whether he thought a release was likely on January 25, McMullen replied: "The way things are going in Egypt, it's really hard to predict what they're going to do … It's quite possible they could continue with the status quo."
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Exact figures of the number of young people who are detained in Egypt are not available, but rights groups agree that there are at least hundreds being held.
"The government has continued to use pretrial detention against any individual or dissident," McMullen said.
"Mahmoud attended a rally; he wasn't someone who was out there - he wasn't very involved in a political movement. He was trying to make a statement. Mahmoud doesn't have political affiliation with any of the parties he has been accused of being part of."
Like many of those being held, the charge Hussein faces - belonging to a "terrorist" organisation - refers to the Muslim Brotherhood, a now-banned group in Egypt.
"Pretrial detention is at an all-time high now," said McMullen, adding that from 2013 to 2014, there was a 360 percent increase in the number of pretrial detainees being held.
Last year, a petition by Amnesty to release the student gathered more than 145,000 signatures from 138 countries.
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In the run-up to the fifth anniversary of the January 25 uprising - which led to the removal of President Hosni Mubarak - Egyptian authorities have stepped up arresting activists.
Egypt has led an extensive crackdown on both Muslim Brotherhood and liberal activists since 2013, when the military deposed Mubarak's successor, the democratically-elected President Mohamed Morsi.
Morsi, who belonged to the Brotherhood, was arrested and put on trial with most of the group's leadership and thousands of its supporters.
Amnesty estimates that the government of President Abdel Fattah el-Sisi - Morsi's successor - has arrested, charged, indicted or sentenced "after unfair trials" more than 41,000 people.
There is a particular concern over cases such as Hussein's, where the defendants are young.
"Freedom of speech is what we accomplished as a result of the January 25 revolution, and it is the only win that young people gained ... They learned how to demand their rights and the rights of others," Tito Tarek, Hussein's brother, told Al Jazeera.
Tito Tarek was also arrested on January 25, 2014, having attended a protest, but was released after more than two months.
"In light of the fact that the other demands of the revolution - bread, freedom, and social justice - did not materialise, freedom of speech is a win we gained from the greatest event that we participated in during modern times, and during which we lost thousands of martyrs.
"As young people, we will not give up our rights to freedom of peaceful speech and opinion and our rights to demand our freedoms."
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He added: "I can assure you that the most difficult feeling in the world is to be detained and then to hear that your younger brother has been arrested and subjected to torture
"It is very hard to get used to the feeling that your younger brother is in jail and so, I miss everything about him, especially because Mahmoud is the closest brother in age to me. I miss us playing and fighting about the littlest things, and I miss the smile that would never leave his face. [I miss] everything."
While he expects his brother to be released at some point, he is unsure that his sibling will be freed on Monday.
"Nothing in Egypt follows a process," he said. "Every day, people are jailed; every day people are arrested. Some people are released, and those who are released don't know why, nor do we know why they were arrested in the first place. But, I can say that I await the day of [my brother's] release.
"The sense of sorrow is coupled with a sense of pride in my younger brother for his ability to endure the extent of this injustice."
Follow Anealla Safdar on Twitter: @anealla
Source: Al Jazeera