Three stages of the Holocaust in Lithuania

 The Holocaust in Lithuania can be divided into three stages: mass executions (June–December 1941), ghetto period (1942 – March 1943), and final liquidation (April 1943 – July 1944). Unlike in other Nazi-occupied countries where the Holocaust was introduced gradually, Einsatzgruppe A started executions in Lithuania on first days of war. Executions of Jews on a mass scale took place in Lithuania before the practice had spread to other occupied countries. (Wikipedia)

Update November 2017: The NOVA film on the Holocaust Escape Tunnels is not just about Richard Freund's amazing non-invasive archaeological discoveries of the tunnel, mass graves, and the Great Temple of Vilna, it is more significantly a "reset" on my understanding of the chronology of the Holocaust. "Holocaust by bullet" is how Tim Snyder describes the first stage. It was the enthusiasm of the Lithuanians to collaborate with the Nazis that emboldened Hitler to formulate the "final solution." The little country no one had ever heard of was of far greater historical consequence than I'd ever realized.
76 men and 4 women spent 76 days digging the tunnel that let them escape the burial pit where they worked. Of those 80, 11 managed to escape into the forest without being shot. At least a few joined Abba Kovner's band of FPO partisan resistance. 

WATCH THIS. Powerful 54 minutes: NOVA: Holocaust Escape Tunnel