REPUBLIKA.CO.ID, GAZA/JERUSALEM - Israel declared a Gaza ceasefire over on Friday and killed more than 50 Palestinians in renewed shelling, saying militants had breached the truce shortly after it began and apparently captured an Israeli soldier.

The 72-hour break announced by US Secretary of State John Kerry and UN Secretary-General Ban Ki-moon was the most ambitious attempt so far to end more than three weeks of fighting, and followed mounting international alarm over a rising Palestinian civilian death toll.

The ceasefire was to be followed by Israeli-Palestinian negotiations in Cairo on a longer-term solution.

Egyptian officials said the invitation still stood, but some Palestinian representatives had asked for a postponement until Saturday or Sunday to allow a new truce to be reached.

The Israeli military said that 90 minutes into the truce - as Palestinian families who had fled neighborhoods that had been turned into battlefields began to trek home - militants attacked soldiers searching for infiltration tunnels in the southern Gaza Strip.

The truce had left Israeli ground forces in place in the Hamas-dominated Gaza Strip and a military spokeswoman had said operations would continue to destroy a warren of tunnels through which the Islamist group has menaced Israel's southern towns and army bases.

Israel launched its offensive in Gaza on July 8, unleashing air and naval bombardments in response to a surge of cross-border rocket attacks. Tanks and infantry pushed into the territory of 1.8 million on July 17.

Gaza officials say at least 1,509 Palestinians, mostly civilians, have been killed and 7,000 wounded. Sixty-three Israeli soldiers have been killed and more than 400 hurt. Three civilians have been killed by Palestinian rockets in Israel.

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