The Siebel Si 204 was a small twin-engined transport and trainer aircraft developed during World War II. It was based on the Fh 104.
Originally designed in response to a RLM development order for a small civil transport plane in 1938, it was eventually produced for the Luftwaffe.
An Si-204 was likely the last German aircraft shot down on the Western Front. At 8 PM on the evening of May 8, 1945, 2nd Lt. K.L. Smith of the 9th Air Force's 474th Fighter Group, flying a P-38 Lightning, downed a Siebel three miles southeast of Rodach, Bavaria.
Source:
Info: Wikipedia
Profile: German Warplanes of World War II
Published by Temple Press/Aerospace.