"There is no chance that this shell caused such damage," the general said.
Israel says its shells could not have caused the explosion on the beach.
Witnesses said two shells landed on the town but caused no injuries.
The other two shells failed to explode and caused negligible damage.
A spokesman said that the 122-millimeter shell struck near a kibbutz but caused no damage.
"So mortar shells cause enormous damage, more than in other areas."
The shells landed in an open field and caused no injuries or damage.
In March 1942, a seven-inch shell struck the 37th floor of the building but caused little damage and no injuries.
The shell struck a forward searchlight above the bridge and caused serious casualties.
The shells killed 250 people and wounded 620, and caused considerable damage to property.
