The Sudanese men in the video clips looked starved and can barely talk, their bodies marked by bruises and cuts.
“The army people hit me with iron rods and told me I was collaborating with the Rapid Support Forces,” said a man who appeared to be in his twenties and gave only his first name, Mohannad.
“I have been in detention for four months. They gave me no food at all for the last three days."
The videos were posted online last month by the Rapid Support Forces (RSF), the paramilitary group that has been fighting against the Sudanese army in Khartoum and other parts of the country since April.
According to the RSF, the men in the videos were held at a key military base in Khartoum that was the scene of some of the war’s fiercest battles last week.
They were freed when RSF fighters seized control of large sections of the sprawling complex housing the army’s Armoured Corps in Al Shagara district.
The authenticity of the video clips could not be independently verified, but the accounts given by the men conform with information given by witnesses and activists about the detention of hundreds of men by the army and the RSF, on suspicion of spying for the other side.
In many cases, the men's families do not know where they are being held. Some of the men are tortured or held in dismal conditions, witnesses and activists said.
The hunt for spies and collaborators in Khartoum is a dirty war waged in almost complete secrecy. It adds a grim layer to the conflict between the army, led by Gen Abdel Fattah Al Burhan, and the RSF, commanded by his one-time deputy and ally Gen Mohamed Dagalo.
The International Criminal Court is investigating the RSF for possible war crimes in the western region of Darfur, where the paramilitary's fighters and allied Arab militias are accused of killing thousands of ethnic Africans in July.
The US on Wednesday imposed sanctions on Gen Dagalo's brother, RSF deputy leader Abdelrahim Dagalo, over rights abuses.
The US Treasury said sanctions were imposed on him for his leadership of "an entity whose members have engaged in acts of violence and human rights abuses, including the massacre of civilians, ethnic killings, and use of sexual violence".
The war in Sudan has caused a major humanitarian crisis, with more than five million Sudanese displaced since April. Millions more are in need of food and medical aid.
Against this backdrop, the warring generals have promised Sudan’s 48 million people that the country will have democratic rule when the fighting ends, as well as justice and equality.
The RSF has sought out active and retired members of the armed forces, as well as people known to have been active supporters of the toppled government of former president Omar Al Bashir and suspected of fighting on the army’s side.
Homes known to belong to army officers or members of Al Bashir’s now-dissolved National Congress Party are targets for RSF fighters. If a suspect is found in the homes, he is arrested and taken away.
For its part, the army hunts for Sudanese who hail from the Arab tribes of Darfur and who typically live in the capital’s outlying districts.
Army soldiers have also been accused of assaulting civilians in neighbourhoods they liberate from RSF control, said Saeed Samy, a US-based expert on Sudan.
“These are two warring armies to which human rights or the prevalence of the law don’t matter,” Mr Samy said.
“The RSF targets members of Al Bashir’s National Congress Party. The army goes after individuals it believes to have collaborated with the RSF when the paramilitary controlled their neighbourhood.
“A pattern has also emerged that army air strikes targeting districts controlled by the RSF and whose inhabitants predominantly share the same ethnicity as RSF fighters leave large numbers of civilian casualties."
Sudanese state television frequently broadcasts names provided by the military of people suspected of spying for the RSF.
The announcements give those on the list a week to surrender.
An army source told The National that the hunt for RSF spies was led by the military intelligence, but that special police units operating in civilian clothes make the arrests.
Spying for the RSF or the army is sometimes used as cover to detain anti-war activists with large followings on social media, residents and activists have said.
The father of a 22-year-old university student told The National how his son was detained by plainclothes security men when he went back to the family home in Khartoum to retrieve official documents to allow his sister to travel abroad.
“Days after he disappeared, we received a text, presumably from one of the security agencies, saying he has been detained. They did not say where or why,” said the father.
The family moved to White Nile state, south of the capital, to escape the fighting.
“A few days later he managed to call us and say he has been beaten, verbally insulted and accused of being a Rapid Support Forces spy," he said.
“I hold Al Burhan and Hemedti [Gen Dagalo] responsible for the safety of my son who is detained on drummed up and false charges.
“My son has no political affiliation, but he is against the war and the destruction it has brought us.”
Osman Al Mirghany, a prominent political analyst, believes most of the blame for the detentions should be directed at the RSF, which he said had an unusually high number of detention centres across Khartoum.
“Arbitrary detentions are not uncommon in war. They have been common in Darfur for the past 20 years, but they are new in Khartoum,” he said.
