Rocket fire from Gaza late last night, near the end of the initial 72-hour truce, and early Thursday morning, as the extension began, raised doubts about whether it would last. Israeli air strikes in response to the rockets added to fears that fighting was ratcheting up again.
But the exchange of fire was limited and did not last long. Quiet returned to the skies over Gaza, aside from the familiar buzz of Israeli drones.
People also tentatively started going back out into the streets, although traffic was not as busy as in previous days of the ceasefire.
The extension of the ceasefire is to last until midnight on Monday.
Israeli and Palestinian officials said they had accepted the extension of the truce after the initial three-day ceasefire expired at midnight.
Israeli government spokesman Mark Regev accused Hamas, the militant Islamic group that holds power in Gaza, of violating the truce with the overnight rocket fire
But Hamas spokesman Sami Abu Zuhri denied that the group had anything to do with firing any rockets toward Israel, leaving it unclear which Palestinian group had launched them.
Israeli and Palestinian delegations have been negotiating in Cairo through Egyptian mediators in an attempt to find a more lasting end to hostilities. Under the ceasefire extension, they are expected to re urn to the indirect talks over the weekend.
"There remains a positive atmosphere towards reaching a comprehensive agreement," Azzam al-Ahmed, the lead Palestinian negotiator told reporters.
"But there are still sticking points."
The demands by the two sides are not easy to reconcile. Israel has said it wants Hamas to disarm and Gaza to be demilitarised while the Palestinian delegation in Egypt, which includes Hamas, has asked for an end to Israel's economic blockade on Gaza, an extension of fishing rights off the coast, the reopening of an airport and seaport and the release of prisoners held by Israelis.
Four weeks of violence has killed 1,939 Palestinians and 67 on the Israeli side since Operation Protective Edge began on July 8.
Al-Ahmed, head of the Palestinian team, said that there is still no agreement on the opening of crossings into Israel, "the launching of a free fishing zone" and various "security issues."
Israel had launched Operation Protective Edge with the stated objective of stopping rocket fire from Gaza on its southern communities. Later it added the destruction of cross border tunnels entering into Israel also among the major goals of the operation.
Israel holds Hamas responsible for all attacks emanating from Gaza as they are de facto rulers of the coastal strip.
Israel's Iron Dome missile defense system has intercepted some of the roughly 3,500 rockets fired from Gaza since the conflict began.
Regev told CNN on Thursday that the key to a longer-term solution was an end to rocket fire from Gaza.
"If there's no hostile fire from Gaza into Israel, of course we can have serious discussions about easing restrictions," he said. They're only there in the first place as a response to the violence."
Hamas is the "wild card," Regev said, expressing skepticism that the group would give up violence.
But Hanan Ashrawi, an executive member of the Palestine Liberation Organization, said the Israelis "keep blaming Hamas for everything."
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