By Nir Hasson and Amos Harel, Haaretz Correspondents, and Haaretz Service Palestinians in the Gaza Strip launched early Saturday 21 Qassam rockets at Sderot wounding three people, the third such attack in as many days. The casualties are three civil guard volunteers who were hurt by shrapnel, Israel Radio reported. One of them was moderately wounded, the other two lightly. They were taken for treatment to the Barzilai Medical Center in Ashkelon. One Qassam fell next to a sports hall in the center of town. Others fell on a school, a factory and a residential building, none of which caused...