The fighting in Ukraine has damaged almost 1,000 school and medical buildings, UN human rights inspectors said on Friday.
Millions of children have had their schooling disrupted as heavy artillery, cruise missiles and rockets caused widespread damage.
Damage to hospitals and clinics has caused casualties among patients, staff and visitors.
Air strikes by Russia on Ukraine's energy infrastructure in winter killed at least 116 civilians, a new report by the UN's Office for the High Commissioner of Human Rights found.
The report said 379 others were injured during the strikes by Russian cruise missiles and Iranian-made drones that hit Ukraine's power supply.
It said inspectors were "gravely concerned" about the legality of Russia's actions given the impact on life, health, education and other human rights.
"The strikes have caused power, heating and water supply outages and disrupted mobile and internet connectivity and railway traffic across the country," they said.
"They have put millions of civilians at risk during the colder months and disrupted education for millions of children in Ukraine."
Schools and hospitals were hit near front lines. At least 325 medical centres have been damaged since Russia invaded, the report said, of which 38 were destroyed.
Many doctors have fled the conflict zones and pharmacies have struggled to obtain supplies, the UN team said.
At least 631 schools have reportedly been affected by the fighting, of which 156 were destroyed.
The true number of civilian buildings damaged is "likely considerably higher", the inspectors said.
Russian forces are blamed for 598 such incidents, while 279 are attributed to Ukraine and dozens of others took place in contested territory.
The Russian air strikes hit an estimated 70 private homes, five apartment blocks, four cultural buildings and 20 other civilian objects.
Ukrainian President Volodymyr Zelenskyy was forced to order power cuts while the grid was repaired during winter strikes.
Kyiv's allies described the barrage as an attempt by Russia to freeze Ukraine into submission.
A separate UN report said war crimes may have been committed in the treatment of prisoners of war by both sides.
It reported 40 cases of summary executions. In other instances, prisoners were beaten, kept in inhumane conditions or had their belongings looted.
Although Ukraine was blamed for 25 of the summary execution cases and 15 were in Russian-held territory, the numbers are not comparable because Moscow refused investigators access to its prisoner of war camps, the report said.
Eleven of the cases in which Russia is implicated involved the mercenary Wagner Group, said Matilda Bogner, head of the UN monitoring mission.