Rights campaigners have urged the Democratic Republic of Congo (DRC) government to investigate allegations of torture and ill-treatment among hundreds of children, reportedly associated with armed groups, that have been arrested and detained. Activists have called on authorities to prosecute those responsible appropriately.

In countries embroiled in civil strife or armed conflict, children may be arrested and detained for reasons of "national security", but their treatment and conditions of detention often violate international legal standards.

In the DRC – where an estimated 70 armed groups behind ongoing violence in the eastern region – children are detained without charge for actual, or suspected, association with these groups.

The stronger militant groups in the eastern parts include the Democratic Forces for the Liberation of Rwanda (Forces démocratiques pour la libération du Rwanda, FDLR) and the Ugandan Allied Democratic Forces (ADF) – which the Council on Foreign Relations says "continue to terrorise communities and control weakly governed areas of the country, financing their activities by exploiting the country's rich natural resources".

The United Nations (UN) estimate at least 2.7 million persons have been internally displaced by the fighting, which has also pushed approximately 450,000 Congolese refugees in other nations.

Hundreds of 'child soldiers' detained in DRC

Citing UN figures, a recent report by Human Rights Watch (HRW) found that Congolese armed forces arrested and detained at least 257 children during 2013 and 2014, accused of being members of the FDLR. While the minors were released after advocacy by the UN, 40% of the children interviewed by humanitarian workers claimed they had been subjected to ill-treatment during their detention.

In December last year, HRW found 29 boys between 15 and 17 detained in what the organisation described as "appalling conditions" in a military prison in Angenga in the northwest. According to the authorities, the boys were members of the rebel armed group FDLR, although none had been formally charged with any crime. Of the 29 boys, 17 said they had never been affiliated with the FDLR while two admitted they were active fighters at the time they were apprehended.

"I was never with the FDLR. One day, I was on my way to the market to buy some things. On my way I ran into Congolese army soldiers, and they arrested me... They transferred me to Bukavu, then Goma, and finally to Angenga," a 15-year old boy told HRW. "I don't know what they want from me. Maybe they just want to say they arrested FDLR. I don't know."

Ten other boys said they had belonged to the group, but had demobilised months or years previously and all reintegrated into civilian life. One of them, a 16-year old, described how the FDLR forcibly recruited him before he managed to escape two months later and surrender to the Congolese army (FARDC).

"I handed myself over to the Congolese army in Kitchanga so the FDLR wouldn't find me," he said. "They put me in prison and now I'm in Angenga."

According to the commander of the Congolese army regiment who carried out the arrests, no children or civilians were among those detained at Angenga. He told HRW all detainees were FDLR fighters "captured on the front lines".

Denied lawyers, detained indefinitely without charge

While some of the boys had been detained for over 12 months, they were all denied access to lawyers, other due process guarantees or protections established under international juvenile justice standards.

The children were held with adult detainees in severely overcrowded cells in Angenga prison, which housed 750 detainees.

"They were co-mingled with adult detainees during the day, and had little access to food, clean water, or medical care," HRW said in its report.

At the time, HRW said it believed the actual number of children detained may have much higher than the 29 interviewed.