JERUSALEM--In the heaviest barrage in more than a year, dozens of rockets were launched at southern Israel from the Gaza Strip on Wednesday, drawing condemnation from Israel's political leadership and swift retaliation by its military.
At least 60 rockets and mortar shells were fired in rapid succession over a two-hour period. At least eight hit urban or open areas, according to Israel's army, while several others were intercepted by Israel's mobile air-defense system, Iron Dome.
There were no immediate reports of casualties.
As the air raid sirens subsided, Israeli residents within about 25 miles of the border with Gaza were instructed to remain within running distance of bomb shelters and concrete-reinforced safe rooms.
After launching aircraft to identify the source of fire, Israel's military first responded with artillery and, according to an army statement, hit "two terrorist targets" in the southern and northern parts of the strip. Israeli airstrikes were also underway, targeting dozens of locations in the Gaza Strip, according to news media reports.
In Gaza, the military wing of Islamic Jihad claimed responsibility for the barrage. In a statement, the organization called it a response to the "crimes of the Zionist enemy in the occupied West Bank and Gaza Strip," the latest of which, it said, was the killing of three of its operatives in an airstrike Tuesday.
According to Israel's military, Tuesday's airstrike targeted the militant squad after it fired a projectile at Israel.
Speaking in the Knesset on Wednesday evening, Prime Minister Benjamin Netanyahu said Israel would not be deterred and would continue defending itself "against the terrorist organizations in Gaza."
In a meeting between President Shimon Peres and visiting British Prime Minister David Cameron, both leaders addressed the flare-up.
"It's a very severe attack," said Peres, who urged the people of Gaza to choose: "It's either peace or violence." He cautioned the Hamas rulers of the Gaza Strip that they "can't have it both ways."
Cameron condemned the rocket attacks as targeting civilians indiscriminately, calling the strikes "barbaric."
The attacks from Gaza illustrate Israel's need for security and should make clear to Palestinians that "there is no violent route" to statehood, which can only be achieved by dialogue and "thorough agreement," Cameron said.
During a special security consultation Wednesday evening, Defense Minister Moshe Yaalon said that if Israel had no calm, neither would Gaza "in such a way that will make Islamic Jihad terrorists regret their shooting."
Yaalon said if Hamas couldn't impose calm, Israel would do it.
Yaalon has ordered the crossings between Gaza and Israel closed pending further security assessments, with exceptions for humanitarian needs.
Wednesday's rocket fire was the fiercest since Israel's weeklong military campaign against Gaza in November 2012 that ended in an informal cease-fire.
A spokesman for Islamic Jihad in Gaza said the attack came in response to aggression "and does not mean the collapse of the cease-fire agreement."
State Department spokeswoman Jen Psaki said the United States condemned the attacks from the Gaza Strip into Israel.
"We call for these terrorist attacks to cease immediately," Psaki said. "Israel, like any nation, has a right to defend itself."