There are also reports that israeli rockets have hit smuggling tunnels on the border with Egypt, without causing casualties.
"This attack came after rockets were fired at Ashkelon," Zyara said.
He said that injuries were less than they could have been, given the crowded area that was hit, because Palestinians expected that "Israel would retaliate" for the attack on Askkelon.
"None of the Palestinian groups declared responsibility for that attack," he said.
Binyamin Netanyahu, the Israeli prime minister, said that "Israel takes the firing on Ashkelon very seriously".