Nearly 8,500 civilians are confirmed to have been killed in Russia's invasion of Ukraine, a U.N. body said on Tuesday, with many thousands more unverified deaths still feared.

The Office of the UN High Commissioner for Human Rights (OHCHR) said it had recorded 8,490 people killed and 14,244 injured between the launch of the invasion of Feb. 24, 2022, and April 9, 2023.

The body has long described its figures as "the tip of the iceberg" because of its limited access to battle zones.

The majority of the deaths were recorded in territory controlled by the Ukrainian government and under attack by Russian forces, including 3,927 people in the Donetsk and Luhansk regions, which have witnessed intense fighting.

"OHCHR believes that the actual figures are considerably higher, as the receipt of information from some locations where intense hostilities have been going on has been delayed and many reports are still pending corroboration," it said in a statement.

Russian forces have pressed their offensive in the eastern Donetsk region where several cities and towns have under heavy bombardment.

A U.N.-mandated investigative body found last month that Russian forces had carried out "indiscriminate and disproportionate" attacks on Ukraine. Russia denies targeting civilians or committing atrocities.