Key developments on May 22: * Ukraine denies Russian claim that drone strike killed civilians in occupied Luhansk Oblast * Ukraine strikes Russia's Yaroslavl Oil Refinery 4 times in month, Zelensky confirms * Russia offers university admission boost for students who pass drone piloting exam * Russian attacks kill 5, injure 52 across Ukraine as Dnipro drone strike leaves dozens wounded Ukraine's General Staff on May 22 rejected Russian claims that an overnight Ukrainian drone strike killed

UN officials warned the war is becoming “deadlier by the day” after major Russian drone and missile attacks across Ukraine.

One wave of strikes hit a Russian drone pilot training camp, killing at least 65 cadets and an instructor, Ukraine claims.