The Palestinian militant group Hamas has announced an immediate ceasefire, giving the Israeli forces a week to withdraw from the Gaza Strip.The leadership-in-exile in Damascus made the announcement on Syrian television, saying the ceasefire also applied to other militant Palestinian groups. The offer comes hours after Israel declared a unilateral ceasefire in the early hours of this morning. The cessation of hostilities has already been tested by fresh rocket salvoes into Israel, one missile struck a house in Ashdod; no-one was hurt. The attack was followed by a retaliatory air strike in which one man was killed near Khan Younis. Hamas had earlier demanded a complete withdrawal of Israeli forces from Gaza and a relaxation of its blockade of the frontier before it would consider halting its rocket fire. Israel says its troops will stay in Gaza for as long as necessary. At least 1300 Palestinians have been killed since Israel launched its offensive on December the 27th according to Palestinian health officials… among them at least 410 children. Another 5,300 people have been wounded. Thirteen Israelis have died.