Eritreans, including Olympian Zeragaber Gebrehiwot, freed after 18 years in jail without trial

Thirteen people who had been detained 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 released are several high-profile figures, including 69-year-old Olympic cyclist and businessman Zirajaber Gebrehiwot.

They were being held in 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 detained in Mai Serwa told the BBC that the prisoners were arrested in October 2007 after an assassination attempt on Colonel Simon Gebredingile, a senior internal security officer in the government of President Isaias Afwerki.

The source said that about 30 people were initially arrested. Some have been released over the years, but about 20 remain in detention.

Zergaber competed in the 1980 Moscow Olympics when Eritrea was part of Ethiopia.

The mountainous country that gained independence from Ethiopia in 1993, It has a strong cycling culture Its cyclists have steadily gained international recognition over the past decade.

Among those released with Zargaber on Thursday were prominent businessmen Tesfalem Mengestep and Bakor Mebratu, as well as the Haapet Mariam brothers – David, an engineer, and Matthews, an engineer.

Six senior police officers and an internal security officer were also released.

The Eritrean government did not issue any statement regarding the releases.

Many of them are sick, which may explain why they are being released now.

Prisoners’ relatives said that they were not allowed to visit the prisoners throughout their detention.

The United Nations and human rights groups have long accused the Eritrean government of committing gross human rights violations, including torture, forced disappearances and imprisonment of tens of thousands of people in inhumane conditions.

Sources told the BBC that Mai Serwa prison, located about 9 kilometers (six miles) northwest of the capital, Asmara, has expanded over the years to include 20 metal shipping containers in which prisoners are held incommunicado.

last year, Berhane Abrahi, who served as finance minister under President Isaias for 11 years until 2012, died in prison. He had spent six years in prison, and was arrested after publishing a book in which he described the president as a “dictator” who needed to resign.

He was also never brought to court. According to the UK-based Human Rights Eritrea, he died in Karsheli Prison in Asmara.

For the past three decades, Eritrea has remained a one-party state without an effective constitution. It is one of the most militarized societies in the world, with military conscription indefinite.

There has been no free press since the closure of independent newspapers and the arrest of most of their editors and journalists in 2001.

This is when the government arrested 15 politicians known as the Group of 15, along with 16 journalists, after they demanded that President Isaias implement the draft constitution and hold open elections.

According to Amnesty International, the fate and whereabouts of 11 politicians, as well as journalists accused of having links to the G15, remain unknown.

President Isaias, 79, celebrated his 32nd year in power earlier this year and has not faced any elections yet.