GAZA CITY: Israel shot down a rocket fired at its commercial capital Tel Aviv on Tuesday, a military source said, the deepest such attack from the Gaza Strip during a two-week-old escalation of fighting in the Palestinian territory.
Live television showed a double-burst of smoke in the clear blue skies above Tel Aviv after air raid sirens sounded.
Hama's armed wing the Ezzedine al-Qassam Brigades claimed responsibility for the shelling of the Israeli capital, Palestinian media reported.
An Israeli source told AFP that the Israeli Army also killed Gaza militants entering Israel by sea.
The Israeli military source said Israel's Iron Dome interceptor shot down the projectile fired by Palestinians, hours after Israel intensified its bombing campaign in Gaza in a declared bid to halt rocket fire pouring into the south of the country.
Earlier a senior Israeli Cabinet minister said that Israel will not halt its military offensive in the Gaza Strip until rocket fire is halted.
Defense Minister Moshe Yaalon warned it was likely to be a protracted campaign.
"We are preparing for a campaign against Hamas, which will not end in just a few days," he said in a statement which defined the aim as being "to exact a very heavy price from Hamas."
Shortly before the interview, the military announced it was calling up additional reservists as it prepared for a possible ground invasion of Gaza. Earlier Tuesday, the army was authorized to activate up to 40,000 reserve troops.
Israeli warplanes killed at least 15 Palestinians Tuesday and wounded at least 90 others, pounding the Gaza Strip in a new campaign to stamp out Hamas rocket fire as the two sides slid toward another major conflict.
Hamas said Tuesday that "all Israelis" would be targeted after a deadly strike on a house in the southern city of Khan Younis killed seven people, among them two teenagers.
"The Khan Younis massacre... of children is a horrendous war crime, and all Israelis have now become legitimate targets for the resistance," Hamas spokesman Sami Abu Zuhri said in a statement, without elaborating.
The Arab League called Tuesday for the U.N. Security Council to hold an urgent meeting to discuss the deadly Israeli air campaign against Gaza, Secretary General Nabil al-Arabi said.
An official from the pan-Arab bloc told AFP that Arabi had "instructed the Arab League's U.N. representative to initiate urgent consultations within the Arab group calling for an emergency security meeting of the Security Council."
Earlier, Palestinian president Mahmoud Abbas asked the international community to "immediately intervene to halt this dangerous escalation which would lead the region to more destruction and instability."
Arabi said he had been "in touch with president Abbas to follow the latest developments in the Gaza Strip" while also continuing "consultations with Arab foreign ministers on this subject."
He denounced the "dangerous Israeli escalation" and warned against its humanitarian consequences in Gaza.
"The continued attacks on Palestinian civilians by Israel is a flagrant violation of international humanitarian law, the Geneva Convention and international resolutions on occupied Palestine," said the Arab League chief.
In the most serious flare-up over Gaza since November 2012, it comes as Israel struggles to contain a wave of violence in Arab towns over the grisly murder of a Palestinian teenager by Jewish extremists.
Abbas asked the world to pressure Prime Minister Benjamin Netanyahu's government.
But Netanyahu was expected to order a "significant broadening" of the operation and instruct the army to "take off the gloves," army radio said, quoting a source close to the premier.
In central Gaza, one man was killed in an air strike west of Nusseirat refugee camp, with medics naming him as Ashraf Yassin.
Witnesses said he was a militant of the Ezzedine al-Qassam Brigades, the armed wing of the Islamist Hamas movement.
Shortly afterwards four men were killed when a missile slammed into a car in the center of Gaza City, the emergency services said, without giving further details.
Three more militants were killed in air strikes Monday, two from the Popular Resistance Committees and one from Hamas. Another five Hamas militants died when a tunnel collapsed near the southern city of Rafah.
The Israeli army said the air force and the navy had struck around 50 "terror sites" overnight in a joint operation which had three aims - returning calm to the south, "eliminating Hamas's capabilities" and destroying Gaza's "terror infrastructure."
It also destroyed the homes of four Hamas militants it accused of firing on Israel.
Around Gaza, dozens of tanks and soldiers could be seen massing along the border, AFP correspondents reported.
So far there have been no Israelis killed. - Agencies