Note:
I swapped the original article at the request of a mod to from a source deemed more reliable, but to avoid confusion when reading the comment section prior to this edit, here is the link to the original article. I chose the Relief Web source listed by some who commented. Cheers!
When OHCHR drops a report like this it means they consider the allegations to be credible. It’s the same level as the news calling someone an alleged murderer after the guy killed someone on national TV. The report in this case is based on witness statements and an investigation done by a human rights NGO out of Europe.