The detention of a female lawyer in Sudan, whose whereabouts are still unknown, is the latest in the authorities' brutal campaign against human rights activists in the context of the conflict in the Southern Kordofan and Blue Nile states, Amnesty International said.
Asma Ahmed, a lawyer and member of the banned opposition party the Sudan People's Liberation Movement-North (SPLM-N), was arrested on 4 May when she reported to the office of the Sudanese National Security Services (NSS) in Khartoum.
Two days earlier, NSS officers had gone to her house demanding that she report to them.
Asma Ahmed has been held incommunicado since her arrest, without charge, placing her at high risk of torture or other forms of ill-treatment. She is diabetic and requires medical care and a special diet.
"The arrest of Asma Ahmed is yet another example of the Sudanese authorities' determination to stifle freedom of association and the work of human rights activists in the country," said Lucy Freeman, Africa Deputy Director at Amnesty International.
"The authorities should immediately grant Asma Ahmed access to a lawyer, and her family, and to charge her with a recognizable criminal offence or release her without delay."
This is the latest in a wave of arrests of individuals, including human rights activists, working in or on Southern Kordofan and other people suspected of being associated with the Sudan People's Liberation Movement - North (SPLM-N).
Many have been detained incommunicado and without charge.
Southern Kordofan and Blue Nile states have been the backdrop of an internal armed conflict between the Sudanese government and the Sudan People's Liberation Army - North (SPLA-N), the armed wing of the SPLM-N, since 2011.
Numerous individuals have been subjected to various forms of ill-treatment and torture when they were detained by the National Security Services in the past year. This has included kicking; beating with sticks, rubber hoses and fists; making detainees stand in scorching heat for days at a time; being deprived of food, water and sleep; and forcing detainees to adopt stress positions.
Amnesty International has also received information that some female detainees have been subjected to sexual violence, including rape.
Amnesty International is not aware of any members of the National Security Service being held accountable for these human rights violations.
In late 2012, 32 women were arrested and detained without charge in Southern Kordofan's capital Kadugli, ostensibly for spying and collaborating with the SPLM/A-N. The majority were government employees working at various ministries in Kadugli and five were detained with their young children, ranging in age from six to 18 months old.
On 27 December, the women and their children were transferred to El Obeid prison in Northern Kordofan. While 14 of them were reportedly released in April 2013, the others reportedly remain in detention in El Obeid. According to information available, the women have not been charged.
On 16 January 2013, the Kuku Centre for Culture and Heritage (KUCCH), and the NINU Centre for Languages and Computer Science, both in Khartoum, were shut down by the Sudanese National Security Services. KUCCH was established in 1993 with the purpose of helping people from Southern Kordofan to preserve their cultural heritage through writing and developing their languages.
In her work as a lawyer, Asma Ahmed has represented many human rights defenders and activists, including Jalila Khamis Koko, a SPLM-N member and an advocate for the rights of displaced people from Southern Kordofan. Jalila Khamis Koko was detained for more than nine months without access to the medical assistance she needed, before being released in January 2013.