Dozens of activists launched a hunger strike on Sunday at the Egyptian Press Syndicate's headquarters in downtown Cairo to protest military rule and the continued detention of dozens of activists by military authorities.
At noon, several journalists and activists formally began the hunger strike, welcoming others to join the campaign in solidarity with their demands.
At 4pm, participants plan to stage a symbolic protest outside the syndicate. At 7pm, protest organisers are expected to hold a press conference to clarify their grievances.
Presidential candidate Khaled Ali, prominent television presenter Reem Magued and leftist MP Ziad El-Eleimy have all announced that they would participate in the rally.
Calls for Sunday's protest came in response to recent statements by several activists that remain in military detention that they plan to stage a hunger strike beginning on 20 May until their respective cases are referred to civil, rather than military, courts.
The activists have been held in military detention since their arrest during 4 May clashes between demonstrators and security forces outside defence ministry headquarters in Cairo's Abbasiya district.
More than 300 were arrested earlier this month following mass demonstrations against Egypt's ruling Supreme Council of the Armed Forces (SCAF). Although a number have since been released, 89 reportedly remain in custody.
Detainees face several charges, including encroaching on state institutions, using violence against military personnel, disrupting traffic, gathering illegally and trespassing on restricted military areas.
The military has repeatedly claimed that the arrests came only after demonstrators had attempted to storm the defence ministry. Activists, meanwhile, accuse military police of using excessive force to disperse demonstrators and referring civilians to military courts.
Egyptian activists have long campaigned for an end to the practice of referring civilians to military tribunals, demanding that all civilians facing military prosecution be referred to civil courts. Some 12,000 civilians are estimated to have faced military prosecution since the SCAF assumed executive power in February of last year following the ouster of former president Hosni Mubarak.
In a statement calling for Sunday's hunger strike, political groups also condemned the alleged mistreatment of detainees in military custody, charging that some had been tortured and deprived of food and medical attention.
Political groups to endorse and participate in the hunger strike include the Justice and Freedom Youth movement; the Socialist Popular Alliance Party; the National Front for Justice and Democracy; the Popular Committees for the Defence of the Revolution; the Revolution Youth Coalition; the Revolutionary Socialists; the Alliance of Revolutionary Forces; the Second Revolution of Rage; the Egyptian Current Party; the Free Islamist Current; the Free Islamist Alliance; the General Islamist Current; the Salafist Front; the 'We are all Detainees' movement; the 'No to Military Trials' campaign; the National Association for Change; the 'Our Rights' movement; the Egyptian Feminist Alliance; the 'Revolution Continues' Alliance; and others.