JERUSALEM, April 28 (Xinhua) -- Israel came to halt to the sound of sirens on Thursday morning to commemorate the six million Jews killed in the Holocaust. At 10 am (0700 GMT), as the two-minute sirens pierced the air, people across the country stood in solemn silence in honor of the six million Jewish victims of the Nazis during World War II. On streets and highways, traffic stopped with many drivers stepping out of their vehicles, standing still in contemplation. Pedestrians halted their steps and stood in silence. In many homes, businesses, and offices people stopped their activity and stood...