 Having gained unprecedented access to numbered prisoner files in 2000, Mesinai was able to place Wallenberg in a series of six missing numbered prisoners, should he have been convicted rather than executed in 1947.That Wallenberg was a numbered prisoner in 1947 was later substantiated by the Russians' admission that he was "most likely" Prisoner Number 7 interrogated one week after his alleged death date.In 2001, the Working Group, which had served under different Soviet/Russian leadership for a decade, was disbanded.