JERUSALEM (REUTERS) - An Egyptian-mediated truce halting the Gaza war went into effect on Tuesday following a surge in cross-border rocket fire into Israel by the Palestinians Islamist group Hamas.

The ceasefire, which is meant to last 72 hours and allow for negotiations in Cairo on a more durable cessation of hostilities, began at 8am local time. (0500 GMT; 1pm Singapore time).

Minutes before, air raid sirens sounded throughout southern Israel and as far north as outlying areas of Jerusalem, triggered by a volley of rockets that Hamas claimed responsibility for. There was no immediate word of casualties.