GAZA CITY - Israeli warplanes kept up deadly raids on Gaza Friday but failed to stop Palestinian militants firing rockets across the border, as the United States offered to help negotiate a truce.
With the violence growing worse, US President Barack Obama in a phone call to Israeli Prime Minister Benjamin Netanyahu said his government was willing to broker a ceasefire.
Obama said he was concerned the fighting could escalate and "called for all sides to do everything they can to protect the lives of civilians", the White House said.
"The United States remains prepared to facilitate a cessation of hostilities, including a return to the November 2012 ceasefire agreement."
The 2012 deal, brokered by former secretary of state Hillary Clinton and Egypt, ended eight days of Israeli airstrikes on Hamas targets in a previous showdown.
Appeals for an immediate truce also came from UN chief Ban Ki-moon at an emergency meeting Thursday of the Security Council, saying a ceasefire was "more urgent than ever".
Russian President Vladimir Putin issued a similar plea in a phone call to Netanyahu, urging an immediate end to the bloodshed and expressing concern over civilian casualties.
Israeli soldiers gather in an army deployment area near the Israel border with the Gaza Strip. PHOTO/AFP
But Israel appeared bent on dealing a fatal blow to the Islamist movement Hamas, which controls Gaza, with Netanyahu reportedly saying talk of a ceasefire was "not even on the agenda".
Israeli air strikes killed more than 30 Palestinians on Thursday alone, many of them women and children.
Hamas, the Palestinian group ruling Gaza, also appeared to have no interest in letting up, striking deep inside Israel over the past 48 hours, with rockets crashing down near Jerusalem and Tel Aviv and even as far away as Hadera, 116 kilometres (72 miles) to the north.
Senior Hamas member and the movement's former Gaza prime minister Ismail Haniya ruled out any backing down by the Islamist movement.
"The enemy (Israel) is the one that started this aggression and it must stop, because we are (simply) defending ourselves," Haniya said in a statement early Friday.
Sirens wailed across Jerusalem for the second time running on Thursday and a series of loud explosions echoed across the city as the Iron Dome anti-missile system shot down two rockets fired from Gaza, the army said.
Canadian chief project of peace activist boat "Gaza's Ark" checks damages to his burnt boat in Gaza City. PHOTO/AFP
Another two crashed down in open areas in the occupied West Bank, witnesses and security officials told AFP.
Hamas claimed firing four missiles at Jerusalem.
Early Friday six Palestinians were killed in two attacks on Gaza, five of them -- including a woman and a seven-year-old child -- in a strike on the home of an Islamic Jihad militant in Rafah, Gaza's emergency services spokesman Ashraf al-Qudra said.
Since the start of the Israeli campaign in the early hours of Tuesday, around 95 Palestinians have been killed and more than 500 injured, according to al-Qudra.
As the number of victims in Gaza rose, Egypt opened the Rafah border crossing, with hospitals in north Sinai placed on standby to receive the wounded, Egyptian state news agency MENA said.
"We are still facing a difficult, complex and complicated campaign," Netanyahu said after a security cabinet meeting.
An Israeli police bomb technician looks at damage caused by a rocket fired from the Gaza strip, hitting the city of Ashdod on Thursday. PHOTO/AFP
Israel has confirmed preparations are under way for a possible ground attack, with tanks seen massing along the border and Netanyahu facing mounting pressure from coalition hardliners to put boots back on the ground in the territory from which Israeli troops and settlers withdrew in 2005.
1090 sites bombed
Since the start of the operation, the Israeli military's biggest offensive on Gaza since November 2012, its forces have hit over 1090 "terror sites".
In the same period, Gaza militants fired 407 mortars and rockets that struck Israel, while another 118 rockets were intercepted, an army spokeswoman said Friday.
Neither side has shown any sign of backing down, and Israel has approved the call-up of 40,000 reservists.
Almost 300 people congregate n Bordeaux to denounce the Israeli military offensive inthe Gaza strip. PHOTO/AFP
A boy holds a Palestinian flag near the Israeli embassy in Athens during a demonstration by Palestinians and supporting Greeks against Israeli air strikes on the Gaza strip. PHOTO/AFP
Analysts said Hamas had a clear aim: to drag Israel into a ground war hoping to inflict heavy casualties on its troops who would likely come under fire from anti-tank missiles and explosive devices.
Militants would also be seeking to capture Israeli soldiers to use as leverage.
In a news conference, Hamas's armed wing the Ezzedine al-Qassam Brigades issued a veiled threat to kidnap soldiers, saying a "ground war will be a chance to free Palestinian prisoners."
Hamas spokesman Sami Abu Zuhri said in a separate statement that Israel would "pay the price for its crimes," saying an Israeli ground assault would be a mistake, calling Israeli troops "cowards."
Meanwhile on Israel's northern border witnesses reported two rockets fired from Lebanon hitting near the town of Metula.
"One projectile hit an open space near Kfar Yuval, between (northern Israeli towns) Metula and Kiryat Shmona," a military spokeswoman told AFP, adding the army did not yet know whether it was a mortar shell or a rocket.
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