Thirteen people held for more than 18 years without trial in Eritrea have been released from a notorious military prison, relatives of the detainees have told the BBC.
Among those freed were several prominent figures, including 69-year-old Olympian cyclist and businessman Zeragaber Gebrehiwot.
They had been held at Mai Serwa prison, known for its harsh conditions and where many of the inmates are believed to be political prisoners.
An unnamed source who was once detained in Mai Serwa told the BBC the prisoners were arrested in October 2007 following an assassination attempt on Col Simon Gebredingil, a senior internal security officer in President Isaias Afwerki's government.
Around 30 people were initially detained, according to the source. Some have been released over the years, but about 20 remained in custody.
Zeragaber competed in the Moscow Olympics in 1980 when Eritrea was part of Ethiopia. The mountainous country, which gained its independence from Ethiopia in 1993, has a strong cycling culture and its cyclists have steadily gained international recognition over the past decade.
Those released with Zeragaber include prominent businessmen Tesfalem Mengsteab and Bekure Mebrahtu, as well as the Habtemariam brothers - David, an engineer, and Matthews, a geometrist. Six senior police officers and an internal security agent were also freed.
The Eritrean government has not issued any statement regarding the releases, though it's possible the ill health of many former prisoners could explain their release now. Families were not allowed to visit throughout their detention.
The UN and human rights groups have long accused the Eritrean government of gross human rights violations, including torture, forced disappearance, and the imprisonment of tens of thousands of people under inhumane conditions.
Mai Serwa prison has expanded over the years to include 20 metal shipping containers in which prisoners are held incommunicado, sources have reported. The environment is highly oppressive, raising severe concerns for those forced to endure long-term solitary confinement.
Last year, senior political figure Berhane Abrehe, who served as President Isaias's finance minister for 11 years until 2012, died in prison after being detained for six years over his criticisms of the government.
Over the last three decades, Eritrea has remained a one-party state with no functioning constitution, becoming one of the most militarised societies, characterized by indefinite military conscription and a pervasive lack of civil liberties.
Since the arrest of independent journalists and editors in 2001, there has been no free press, with serious repercussions for those who dare to criticize the regime.
At 79, President Isaias Afwerki has held power for 32 years without facing an electoral challenge.
