Israeli warplanes pounded the Gaza Strip on Wednesday after the first rocket fire from the Palestinian territory in weeks hit an Israeli city, in a blow to efforts to avert a new war. Gaza's Islamist rulers Hamas disavowed the rocket fire saying they rejected "all irresponsible attempts" to undermine Egyptian efforts to broker a new long-term truce. But Israel, which holds Hamas responsible for all rocket fire from the territory regardless of who launches it, struck 20 targets in Gaza, killing one Palestinian, according to the Hamas-run health ministry.
Israel also closed both its border crossings with Gaza in reprisal, further isolating the blockaded enclave where deteriorating living conditions have stoked violent protests along the border.
Gaza militants fired two rockets before dawn, one of which caused damage to the garden of a family home in the southern city of Beersheba, 40 kilometres (25 miles) away, the Israeli army said.
The family of three children escaped injury but were treated for shock at the scene, Israeli media reported.
"At 4:00am (0100 GMT), Israelis in the city of Beersheba were running to bomb shelters after a rocket was launched from the Gaza Strip at Israel," the army tweeted.
"We will defend Israeli civilians," it added.
The other rocket came down in the sea off Tel Aviv, 70 kilometres (45 miles) from Gaza, the army said.
Army spokesman Jonathan Conricus was dismissive of the disavowal of the rocket fire by Hamas and its allies, saying the group bears "full responsibility" for the medium-range rockets fired.
"Only two organisations in Gaza have these specific types of rockets... Hamas and Palestinian Islamic Jihad," he said, referring to a group closely allied to Hamas.
"Which of the organisations (fired) is not relevant from our point of view."
In response, Conricus said they struck 20 targets in Gaza including a Hamas attack tunnel and an "advanced weapons manufacturing site."
One Palestinian the army said was preparing a rocket launch was killed in northern Gaza.
The Gaza health ministry identified him as Naji al-Zaaneen, 25. It did not give further details.
The army produced a video showing a man near the border preparing a rocket for launch before being hit by a missile strike.
Border crossings closed
Defence Minister Avigdor Lieberman ordered the closure of both of Israels border crossings with Gaza, making the heavily restricted Rafah crossing with Egypt the enclaves sole gateway to the outside world.
Lieberman also ordered the the reduction of the permitted fishing zone along the Gaza coast to three nautical miles, the defence ministry body responsible for Palestinian civil affairs, COGAT, said.
Lieberman already suspended deliveries of fuel that had been trucked daily into Gaza under a deal brokered by the United Nations.
It had seen thousands of litres (gallons) of fuel paid for by gas-rich Gulf state Qatar delivered to boost power generation in the impoverished territory.
The United Nations says Israels 11-year blockade has resulted in a "catastrophic" humanitarian situation.
Gazas two million residents endure routine power cuts and a chronic shortage of safe drinking water, and more than two-thirds are dependent on international aid.
Egyptian and UN mediators have been trying to broker a deal that would see Israel ease the blockade in exchange for a long-term truce with Hamas.
The latest flare-up comes after months of Palestinian protests along the Gaza border that have drawn a deadly response from Israeli troops.
At least 207 Palestinians have been killed since the protests began on March 30.
One Israeli soldier has been killed by Palestinian sniper fire over the same period.
The protesters have been demanding an end to Israels crippling blockade and the right of return to land now inside Israel, from which their families were expelled or fled during the 1948 war that accompanied its creation.
Lieberman said Tuesday that the protests could not be allowed to go on.
"We are not prepared to accept the level of violence we see week after week," he told troops and commanders at an army base near the Gaza border.