Palestinian militants fired a Grad into Ashkelon on Tuesday, the first such rocket to be fired into the city from Gaza since a cease-fire ended Israel's 22-day offensive in the coastal territory last month.
Three people were treated for shock after the attack, which also caused damage to property.
The rocket strike came after a Hamas delegation met with senior Egyptian officials in Cairo on Monday in an effort to reach an agreement on a truce with Israel.
Ashkelon Mayor Benny Vaknin told Israel Radio that a Grad rocket "struck the heart of a residential neighbourhood".
"Luckily, it landed in an open area," he said.
Ashkelon was hit by nearly 100 rockets during the Gaza fighting. Following Tuesday's rocket attack, a local parents union called for classes to be called off. But city hall announced that school would be open as usual.
The city is 12 km from coastal Gaza, beyond the reach of the improvised rockets often fired by the Palestinians. Factory-produced Grads, which are smuggled into Gaza through tunnels or by sea from neighboring Egypt, have a longer reach.
"To the best of my knowledge, when it's a Grad rocket, it's from Hamas," Vaknin said.
On Monday evening, a Qassam rocket struck an open area in Sha'ar Hanegev, causing neither casualties nor damage. Three mortar shells also hit the Eshkol region earlier Monday, also causing no injuries or damage.
In response to the mortar attack, the Israel Air Force bombed a car in the southern Gaza Strip. Palestinian medical workers reported that one person had been killed in the bombing, and three others were wounded.
The Israel Defense Forces said it targeted gunmen who had fired the mortars.
Witnesses said the air-strike hit the men while they were traveling in a car in the town. Their identities were not immediately known.
On Sunday Israel suffered the heaviest barrage of rocket and mortar attacks since the cease-fire took effect.
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