The M23’s origins are tied to these tensions – it is the latest incarnation of a rebel group that says it is fighting for the interests of the minority Tutsi community in eastern DR Congo.

Its first uprising more than a decade ago ended with a peace deal – when its fighters disarmed and mainly moved into camps in Uganda.

But three years ago, they began leaving the camps saying the deal was not honoured and within a couple months was seizing territory.

The UN peacekeeping mission – first deployed in 1999 – is not mandated to go on the offensive. Two regional forces – an East African one followed by a southern African one – specially deployed over the last few years at the request of Tshisekedi have failed to contain the M23.

This gives an indication of the M23’s sophisticated operations.

According to the UN group of experts, this includes five months of training at the M23’s main base in Tchanzu, hilly terrain not far from Rwanda’s border, that incorporates courses on theory and ideology and then practical elements including “war tactics”, “engagement rules” and “bush tactics”.

It said Rwandan officers were often at the camp, where recruits, including children, were brought – some joining up on a voluntary basis, others forced to do so in a systematic operation where local chiefs had to provide conscripts.

The experts said Sultani Makenga, who once fought for Kagame in the early 1990s in Rwanda and is now the M23’s military chief, attended some of the passing-out ceremonies between 25 September and 31 October 2024 that involved 3,000 recruits.

Rwanda’s spokesperson Yolande Makolo did not address the question of whether Rwandan officers were in the M23 camp but she did deny the charges about child soldiers, telling the BBC last year: “The claim about recruiting minors in camps is absurd, it’s blatant information warfare against Rwanda.”

However UN expert reports detail how the M23’s strength has grown since May when numbers were put at around 3,000.

The experts estimate that between 3,000 and 4,000 Rwandan army troops are on the ground in DR Congo – saying it based this on authenticated photographs, drone footage, video recordings, testimonies and intelligence.

Captured M23 fighters said that the Rwandans were known as the “Friendly Force”, with the experts’ December report saying the English term was “generically used” even when interviewees were speaking in other languages.