Manuel Baptista Chivonde Nito Alves, the 17-year-old detained in Luanda since 12 September, began a hunger strike on Sunday, November 3.
His health has been deteriorating in the 54 days that he has been held in custody with no formal charge.
Journalist and human rights defender Rafael Marques de Morais has sent an urgent appeal regarding Nito Alves to the United Nations High Commissioner for Human rights and to the African Union Human and People's Rights Commission.
"Nito Alves is being detained in an illegal manner and is being subjected to cruel and inhumane treatment in violation of national and international law. I therefore call upon these international institutions to press Angola, as a member state, to free the young man immediately," Marques said.
The Angolan National Police kept Nito Alves in solitary confinement for about three weeks. During that time, prison guards threatened to kill him and the police did not allow him contact with his family. Nito Alves has still not been formally charged and his lawyers have not had access to his case file.
In his appeal to the international organisations, Marques also drew attention to Nito Alves's deteriorating health, as a result of the insanitary conditions in which he is being held. He has received no medical attention.
Marques says the illegal detention and the cruel treatment to which Nito Alves has been subjected are politically motivated. The youth was detained for allegedly ordering the printing of 20 t-shirts with the slogan "José Eduardo out! Disgusting dictator." He has been the target of political persecution since 2011, when, aged 15, he stared to express opinions openly against the regime of President José Eduardo dos Santos.
Other groups have sought to defend Nito Alves since his detention in September. The Angolan Bloco Democrático (BD) party has launched a campaign under the slogan "let Nito attend his school exams". The teenager is in the eleventh grade and risks failing the school year. The BD youth launched the campaign on Sunday with a candlelit demonstration in Luanda's Largo Primeiro de Maio square, calling on the authorities to let Nito Alves attend the school exams that started this week.
Amnesty International has launched an international campaign, calling on its members to write to President dos Santos to demand the immediate and unconditional release of Nito Alves. The news websites Maka Angola and Club-K and the Angolan human rights law centre Mãos Livres are circulating a public petition demanding his release.
Member of the European Parliament Ana Gomes also has also taken up Nito Alves' case. On 17 October she wrote to the chairman of the European Commission, Durão Barroso, and the High Representative of the European Union for Foreign Affairs, Catherine Ashton. In her letter she asked if the EU delegation in Angola had visited Nito Alves in prison and if the European authorities had put any pressure on the Angolan government to free the teenager.