The US called on Rwanda Tuesday to stop its support for the M23 rebels in neighboring Democratic Republic of Congo (DRC).
"We call upon Rwanda to immediately end any support for the M23 (and) withdraw military personnel from eastern DRC," said State Department spokeswoman Jen Psaki.
The human rights group said that rebels recruit men and boys by force.
Read the report here.
It also comes just two days before Secretary of State John Kerry will chair a special session of the United Nations Security Council on Africa's Great Lakes region.
Human Rights Watch said that M23 has carried out numerous war crimes in the region against those they perceive as loyal to the Congolese government and pro-government militias.
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"What we’ve documented is that war crimes committed by M23 fighters have continued since March, and those crimes include summary executions of at least 44 people and rapes of at least 61 women and girls, and forced recruitment of scores of young men and boys," said Ida Sawyer, lead author of the report.
The HRW report documented numerous instances of civilian murders for not giving up sons to the rebel group and others for refusing to give the group money.
The report also says that Rwanda's support for the group has been shrinking.
M23 has faced internal strife in recent months leading to the defeat and then capture of rebel leader Bosco Ntaganda, who is now being held at the International Criminal Court in the Hague.
His rival and new M23 leader Sultani Makenga has continued the human rights abuses in the region since his victory.
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