Two rockets landed in town, near a school and next to a warehouse, and caused some damage. Security forces were attempting to pinpoint the landing site of another rocket that apparently fell in a residential area. One rocket landed in the Strip, while the others landed in open areas outside Sderot.
No injuries were reported in the night barrage, but at least one local resident suffered from anxiety and was being treated by paramedics at the scene.
Two additional rockets were fired early Thursday. One of the rockets landed outside Sderot and the other fell in Palestinian territory. There were no reports of injuries or damage.
The "Color Red" alert system was activated to warn of incoming rockets and residents in the area reported hearing explosions moments before the Qassams landed in town.
The Islamic Jihad claimed responsibility for firing the rockets, saying that the barrage was an "initial response" to the killing of four terrorists in Bethlehem.
IDF forces attacked a Qassam launching pad in the northern Gaza Strip on Wednesday night, as Palestinians were preparing to fire rockets at Israel. The launching pad was reportedly destroyed.
First rocket attack since Tuesday
Wednesday night's barrage marks the first rocket attack since mid-day Tuesday, when Palestinians in Gaza fired a rocket at Ashkelon shortly after Prime Minister Ehud Olmert visited the southern city.
During his visit, Olmert said that rocket attacks on Ashkelon are likely to continue.
"This has been Israel's reality for the past 60 years, and this demands restraint as well as strength," the prime minister told board members of the Barzilai Medical Center in the city."The Grad is heavier than the Qassam, and we have no way of preventing these things (rocket attacks) from recurring."
The prime minister later visited a school in town, where he discovered that students had no time to reach bomb shelters and were using their desks as the only defense against incoming rockets.
Olmert asked the children to demonstrate what happens when a Color Red alert sounds, prompting the children to vanish under their desks in seconds.
Hanan Greenberg, Zeev Trachtman and Reuters contributed to the report