Former militants were recruited by the Democratic Republic of Congo government for a bloody crackdown on protests against the president that left dozens of people dead last year, a rights group alleged Monday.
Human Rights Watch said President Joseph Kabila's regime had drafted in fighters previously active in the M23 rebel group from Uganda and Rwanda to suppress the December 2016 demonstrations, which erupted when he refused to step down at the end of his term in power.
The right group's allegations came as the country faces a new flare-up of violence after Kabila pushed back a much-delayed new vote until December 2018, with the opposition demanding that the veteran leader resign sooner.
"Senior security force officers in the Democratic Republic of Congo mobilized over 200 former M23 rebel fighters from neighboring countries to quash protests against President Joseph Kabila in December 2016," HRW said in a report.
It said Congolese security forces acting with M23 fighters killed at least 62 people and arrested hundreds more as the protests swept through the vast African country between 19 and 22 December 2016.
M23, a mostly ethnic Tutsi rebel group, was defeated in November 2013 at the hands of Congolese and UN forces. Hundreds of fighters fled the country but officials and residents in the eastern region of Kivu have said they had seen militants return.
Congo's resource-rich eastern provinces have suffered years of brutal conflict, with neighbouring states backing rebel groups in a civil war against Kinshasa's authority, and roaming armed militia triggering the mass flight of terrorised civilians.
HRW said its research was based on more than 120 interviews and that during the protests, "M23 fighters patrolled the streets of Congo's main cities, firing on or arresting protesters or anyone else deemed to be a threat to the president".
"Covert operations to recruit fighters from an abusive armed group to suppress any resistance show how far President Kabila and his coterie are willing to go to stay in power," said Ida Sawyer, the organisation's Central Africa director.
"Congolese officials should end all unlawful use of force against protesters and allow peaceful political activities by activists and the political opposition."
Opposition forces are demanding Kabila -- who took office after his father Laurent was assassinated in 2001 -- step down on December 31, but authorities made several arrests ahead of an opposition march earlier this month.