Leib Arie Najmark was born in Warszawa, Poland in 1900. He was a merchant and married to Malka. Prior to WWII he lived in Warszawa, Poland. During the war he was in Warszawa, Poland.
Leib Arie was murdered in the Shoah (according to this source).
This information is based on a Page of Testimony (displayed here) submitted by his son, Yisrael Neimark
During the Shoah, Jews were murdered in a variety of ways, among them gassing, shooting, burning, drowning or burial alive, exhaustion through forced labor, starvation, epidemic diseases, deprivation of medical care and minimal hygienic conditions, and more. Some Jews took their own lives in order to escape arrest and further persecution, or to end their hopeless, relentless suffering.