Nearly 1 million Russian soldiers have been killed or injured in the country’s full-scale invasion of Ukraine, according to a new study, a grisly measure of the human cost of Russian President’s Vladimir Putin’s unprovoked three-year assault on its neighbor.

With high casualty figures and the slow pace of Russia’s territorial gains, President Vladimir V. Putin could face years more of a grinding war of attrition in Ukraine.

A new Center for Strategic and International Studies (CSIS) report estimates approximately 1.4 million total military casualties in the Russia-Ukraine war, with Russian losses nearing one million (around 250,