It happened immediately after StG77 under command of major count Shenborn has landed after their first flight that day (22.06.1941) - Soviet bombers has appeared from nowhere. Nobody knew where they came from - from some distant airfields, from the ones that just were attacked or from some undetected ones.

But still, they were coming - waves of 10, 20, 30 twin-engine bombers in close formation. They even were able to drop some bombs - but not many, very soon appeared Luftwaffe fighters and all of the bombers were destroyed. It were strange, hopeless attacks, bombers were holding straight on course, without any manoeuvres to avoid AA or fighters. They had awfull losses, nobody came back home. But when German fighters were destroying 10 bombers, it were coming 15 more.
Squadron commander capt. Herbert Pabst from 6/StG77 has reported: “They were coming till the end of the day. Only near our airfield we saw 21 bombers crash sites. Not a single bomber survived.”

Source: Cajus Bekker “The Luftwaffe War Diaries”