Pushing forward in rain, the III Panzerkorps advanced half of the way to Kupyansk on the first day and began to turn three divisions, with Generalmajor Wilhelm von Apell’s 22nd Panzerdivision in the lead, toward the south. The XLIV Corps seized a bridgehead over the Donets river. During the morning of the following day, however, all along the front between Kupyansk in the north and Izyum in the south, Soviet units were on the march to the east in the direction of the Oskol river. Overrunning some of these retreating units, Generalleutnant Hans-Valentin Hube’s 16th Panzerdivision entered the north-western part of Kupyansk by the fall of night. Late in the afternoon of 24 June, as it drove to the south, the 22nd Panzerdivision met the leading elements of Generalleutnant Erich Diestel’s 101st leichte Division advancing to the north, at Gorokhovatka on the Oskol river to the north-east of Izyum, and 'Fridericus II' had been completed. By 26 June the Germans had cleared the last pockets of Soviet troops, and the 1st Panzerarmee's bag of prisoners in 'Fridericus II' reached 22,800 men.
Speaking of what the Germans did to the Soviets:
https://twitter.com/Januszbazin1995/status/1568289613327785986
https://codenames.info/operation/fridericus-ii/