Israeli Prime Minister Benjamin Netanyahu yesterday vowed to ramp up a campaign against Gaza militants which has so far claimed 43 Palestinian lives.
"We have decided to further intensify the attacks on Hamas and the terror organisations in Gaza," his office quoted him as saying after consulting defence chiefs in southern Israel.
The offensive has set off the heaviest fighting between Israel and the Islamic militant group Hamas since an eight-day battle in November 2012.
Militants have unleashed rocket salvoes deeper into Israeli territory than before, and Israel mobilised thousands of forces along the Gaza border for a possible ground invasion into the Palestinian territory.
Israel's defence minister warned the offensive would be long-term. "The operation against Hamas will expand in the coming days, and the price the organisation will pay will be very high," Defence Minister Moshe Yaalon said.
Since the offensive began on Tuesday, Israel has attacked more than 400 sites in Gaza. The strikes came after militants fired more than 160 rockets at Israel, including one that reached the northern Israeli city of Hadera for the first time. The city is about 100 kilometres from Gaza.
Israel also claims to have foiled an audacious amphibious assault when Palestinian militants emerged from the sea north of Gaza. In footage of the incident released by the Israeli military, two figures are seen walking out of the surf on an Israeli beach north of Gaza near Zikim. At least four militants are then seen running over sand dunes apparently carrying weapons before being targeted and "neutralised" by Israeli missiles.
The army said it attacked more than 160 sites in Gaza by early yesterday.
Gaza health official Ashraf al-Kedra said yesterday's air strikes killed one militant in south Gaza, an 80-year-old woman, the son, wife and neighbour of a Hamas militant, and three others whose affiliation was not known.
Israel's army said it targeted a militant with the Islamic Jihad militant group who had launched rockets towards Israel. Islamic Jihad claimed that one of its militants was killed with his mother and four siblings, but Kedra said they were all civilians.
About 2,000 people attended a funeral for eight Palestinians, including at least one militant, four adults and two children, who were killed on Tuesday.
In the attack, an air strike flattened the home of a Hamas militant in the southern Gaza town of Khan Younis. Israel's military said it had called the home shortly before the air strike to warn civilians to leave.
A security official said the army has been telephoning homes, or firing small projectiles dubbed "knock on the roof", to warn civilians to leave buildings before demolishing homes.
Israel and Hamas are bitter enemies and have fought numerous times. Until recently they had been observing a truce that ended hostilities in 2012.
Tensions have been rising since the kidnapping of three Israeli teenagers in the West Bank on June 12. Israel accused Hamas of being behind the abductions.
The situation deteriorated last week after the bodies of the three were found, followed a day later by the abduction of a Palestinian teenager in Jerusalem - who was later found burned to death.
Associated Press, Reuters,The Guardian
Kidnapped Israeli trio were shot 10 times with silenced gun: US official
Three Israeli teenagers abducted by Palestinians in the occupied West Bank last month were shot at least 10 times with a silenced gun in what appeared to be premeditated killings, a US official involved in the investigation said.
The disclosure clashed with speculation by some commentators that the captors had intended to take hostages for a prisoner exchange but panicked and shot them.
One of the victims, 16-year-old Naftali Fraenkel, also held American citizenship.
Missing since hitch-hiking home on June 12, their bodies were discovered on June 30.
The FBI, whose mandate includes Americans abducted abroad, received a recording of a distress call made by Gil-Ad Shaer, 16, within days and sent it for audio analysis in the United States. Distorted, tinny reports heard on the tape after an Arabic-accented male voice shouts "Head down!" in response to Shaer's attempt to raise the alarm were found to be consistent with shots from a silenced firearm, the official said.