Here is a good site on captured Allied bombers being used by the germans with a few descriptions on friendly fire incidents

KG200 Site - The Real KG200 - Allied Planes Used

wiki's information on Kampfgeschwader 200 (KG 200)

Kampfgeschwader 200 (KG 200) (Battle Wing 200) was a secret Luftwaffe bomber unit during World War II. The unit was the Luftwaffe's special operations wing that carried out long-distance reconnaissance flights, tested new aircraft designs and tested and flew special missions with captured aircraft.

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They shall grow not old as we that are left grow old Age shall not weary them, nor the years condemn
At the going down of the sun and in the morning
We shall remember them. Lest We Forget