The fragile and brief peace between Israel and militant Palestinians was shattered today in a blast of rocket and air attacks.
The Islamic Jihad group in Gaza fired more than a dozen rockets at southern Israel after Israeli undercover forces killed one of its West Bank leaders.
Israel replied with an air attack on the rocket launchers.
The fresh violence highlighted the fragility of efforts to move Israel and Gaza's Islamic Hamas rulers toward an informal truce.
A dozen rockets and three mortars were fired, two hitting a warehouse and soccer stadium in the town of Sderot, but no one was injured, the Israeli military said.
The rocket barrage from Gaza was expected after Israeli undercover forces opened fire on the car carrying Islamic Jihad leader Mohammed Shehadeh, accused of planning suicide bombings that killed dozens of Israelis.
Israel held Hamas responsible for today's attacks because it controls the Gaza Strip.
"When another group takes responsibility for a rocket launch, they are subcontracting out for Hamas," a government spokesman said. "No one could be firing rockets from Gaza without the support of Hamas."
Former Israeli Deputy Defence Minister Ephraim Sneh said Hamas had to be toppled to stop the rocket fire.
"Israel will not exist side by side with this Iranian entity three kilometres from Sderot and 10 kilometres from Ashkelon.
"There can be no solution without a diplomatic agreement, and there can be no solution without the military wiping out Hamas," he said.
The latest spiral of violence began just hours after Hamas' prime minister in Gaza called for a period of calm with Israel, laying out conditions that would imply limited international acceptance of Islamic militant rule in Gaza.
The offer by Gaza Prime Minister Ismail Haniyeh had come amid growing signs that Israel and Hamas were moving closer to a cease-fire, including an ebb in fighting after clashes in late February and early March that killed more than 120 people, nearly all of them Palestinians.
Israel has warned repeatedly that Hamas would use any lull to rearm.
"We are not in a situation of a (truce) arrangement here," Israeli Defence Minister Ehud Barak said.
"We are in the midst of operations aimed at stopping rocket fire. There is no change in what we're doing. What awaits us here is more operations."Reuse content