Indeed, one of the most notorious war criminals in "Judenfrei" Estonia was Idel Jakobson[1], a Latvian Jew, who in the 1930s tried to overthrow the democratic government, but got arrested and imprisoned. He was freed under 1938 general amnestia and left the country. Returned in 1940 with invading forces as a NKVD officer. In that role, he tortured and executed hundreds of notable public figures, including many Jewish businessmen. Excavations at mass execution sites have shown that his modus operandi was shooting his victims right in the face. The fact that Jakobson was still alive was discovered in 1996, but he died before the massive case against him could be brought to court.

[1] https://en.wikipedia.org/wiki/Idel_Jakobson