A United Nations human rights commission said Friday its initial investigation into Russia's invasion of Ukraine has found evidence of war crimes.

Why it matters: Based on its investigation, the International Commission of Inquiry on Ukraine concluded that war crimes have been committed in Ukraine in the roughly seven months since Russia invaded. The commission did not specify who was responsible for allegedly committing the offenses.

• The UN Human Rights Council voted to set up the independent international commission about a week after the start of the invasion.
• The council currently estimates that at least 5,916 civilians have been killed and 8,616 have been injured during the invasion, though it stressed that its estimates are likely to be far lower than the actual figures.

What they're saying: Erik Møse, chair of the commission, said Friday it investigated four Ukrainian regions — Kyiv, Chernihiv, Kharkiv and Sumy —visited 27 towns and settlements and interviewed more than 150 victims and witnesses to arrive at its findings.

• "We have inspected sites of destruction, graves, places of detention and torture, as well as weapon remnants, and consulted a large number of documents and reports," Møse said.
• "A number of the attacks we investigated had been carried out without distinguishing between civilians and combatants," he said. "This included some attacks with cluster munitions or multi-launch rocket systems and airstrikes in populated areas."
• "As for violations against personal integrity, we were struck by the large number of executions in the areas that we visited. The Commission is currently investigating such deaths in 16 towns and settlements. We have received credible allegations regarding many more cases of executions, which we are documenting further."
• "Common elements of such crimes include the prior detention of the victims as well as visible signs of executions on bodies, such as hands tied behind backs, gunshot wounds to the head, and slit throats."

The commission said explosive weapons used in populated areas are "a source of immense harm and suffering for civilians."

• Investigators found damaged or destroyed residential buildings, schools and hospitals, while entire areas of Kharkiv city were "devastated."
• Some Russian soldiers committed sexual and gender-based violence, the commission reported, citing instances of "sexual violence, torture, and cruel and inhuman treatment."
• "There are examples of cases where relatives were forced to witness the crimes. In the cases we have investigated, the age of victims of sexual and gendered-based violence ranged from four to 82 years."

The big picture: Investigating and prosecuting war crimes can take years, often leading to frustration for victims, Axios' Laurin-Whitney Gottbrath reports.

• The conflict could escalate further after Russian President Vladimir Putin ordered a "partial mobilization" of an estimated 300,000 citizens for the invasion, though the actual number could be much higher.
• Russian-occupied areas of Ukraine also began voting in referendums on the joining Russian Federation Friday. Ukraine and many other countries have denounced them as "sham" votes.
• Putin's mobilization order sparked anti-mobilization and anti-war protests in several Russian cities, leading to the detention of over 1,300 people.

Go deeper: What counts as a war crime and why they're so hard to prosecute