A Palestinian worker looks out of Al Awda food factory, which witnesses said was shelled and torched by the Israeli army during the offensive in the central Gaza Strip. (Ibraheem Abu Mustafa/Reuters)

The owners of the largest factories in Gaza, whose operations were destroyed by artillery shells and airstrikes, say Israel intentionally targeted the industrial sector to bring Gaza’s economy to its knees.

Their charge could be difficult to prove, but hundreds of factories — including producers of ice cream, paver tiles, soft drinks and cardboard cartons — appear heavily damaged in a wave of destruction greater than in the past two wars in Gaza combined.

Israeli military officials say they targeted only factories that were sources of hostile fire, but they have yet to produce detailed evidence to bolster the claim.

Private-sector leaders braced themselves for further losses Wednesday as Hamas and Israel vowed to continue to fight.

At his food cannery, Ayman Hamada walked last week through the charred remains of his life’s work. He employed 150 workers and produced the most popular tomato paste in Gaza. The $5 million factory was still smoldering.

“I’m 45 years old. To be honest, I always thought of the Israelis as having morals and good sense. This time, I am positive, they hit our factories with intent, with a clear eye,” Hamada said. “The Israelis don’t make these kinds of mistakes.”

During the war, Hamada’s house was damaged by an errant Israeli round. He said he got a phone call from one of his contacts in the Israeli military’s economic division apologizing. His sister was killed in Gaza City in an airstrike. “They didn’t call about her,” he said.

At his offices in downtown Gaza City, he fast-forwarded through hours of time-stamped video taken by his five security cameras.

“You see it is completely quiet. No fighters are inside my factory. No rockets are being launched. I make tomato sauce, not rockets. Now, wait for it, here,” he said as he slowed the recording to show bright explosions and then raging fire.

Hamada was mourning for his sister — and his business. “I am a rich guy. Believe me, I have money, a nice house, a fancy car. Everything you could want,” he said. “But I don’t care anymore. Kill me. Drop a bomb on my head.”

Leaders of the private sector in Gaza say they are squeezed between a hostile Egypt, militants in Hamas and Israel, which enforces trade and travel restrictions and prohibits Gaza from operating an airport or seaport. Gaza has so few exports they are not worth counting.

The economy already was choking before the Islamist militant group Hamas began firing rockets. The top U.N. envoy in the Middle East, Robert Serry, said destruction here is three times as great as in the 2009 war between Hamas and Gaza. The Gaza Chamber of Commerce warns that unemployment could soar to 50 percent.

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Israeli military officials insist that factories were legitimate “military targets” because the facilities produced munitions, served as fire bases, or harbored weapons or combatants. Gaza industries are massed alongside the border with Israel, which became the front line.

“We did not have a policy of hitting factories,” said Lt. Col. Eran Shamir-Borer, head of the strategic affairs branch in the international law department at the Military Advocate General’s Corps. “You can’t just hit the economy of the enemy.”

Shamir-Borer said such targeting could be a violation of international law and a war crime. The Israeli military organized fact-finding assessment teams that are reviewing “dozens of cases” with high numbers of civilian deaths, for example, or a strike at a “sensitive site” such as a school, hospital or factory.

International law requires belligerents to take into account the principle of “proportionality,” meaning an army must weigh a military objective against possible collateral losses.

Israel has not offered proof that the large factories it hit produced munitions. Maps released by the Israel Defense Forces show multiple “combat posts” and “hideouts” allegedly used by Hamas but do not include enough detail to show whether the targets were inside or abutting factories.

Israeli surveillance drones were overhead throughout the conflict, and such evidence may be forthcoming. Israel is also preparing to defend itself before international investigations that already have begun. It is not a war crime to make a mistake.

Israeli military officials blame the high number of civilian deaths on Hamas, which operates its militia in a dense urban environment, and according to the Israelis, employs “human shields.”

In its latest count, the United Nations reports that 1,975 people were killed by Israeli fire, most of them civilians. UNICEF says that 457 of the dead were children. Israeli military officials say they killed approximately 900 “terrorists.”

On the Israeli side, 64 soldiers and three civilians, including one foreign worker, were killed.

Much of the world’s focus has been on civilian deaths, but factory owners say that without work, Gaza will slip further into despair, which will bolster extremists.

“The economy was a target,” said Ali El Haik, chair of the Palestinian Businessmen Association. “In the third week of the war, the Israelis shifted fire to the industrial sector.”

Haik waved a list of 202 factories hit but said it was incomplete. He estimated the final number could double. He declined to share his list with a reporter.

“This was not an accident. This was a plan,” said Hatem Hassouna, manager for his family’s contracting and trade company.

“You could argue damage to a few factories is normal in a time of war. But look at the numbers. The strategic assets,” Hassouna said.

His family’s $6.5 million factory employed 230 workers and produced road pavers and cement. Hassouna said none of the company’s cement was diverted to Hamas tunnels, which he said were constructed with materials smuggled into Gaza from Egypt.

“We do not produce military items. Our owners do not support any political party. Our customers are U.N. organizations and projects approved by the Israelis,” Hassouna said.

The Hassouna factory was occupied by Israeli forces on the first day of the ground offensive. “We felt the factory was safe because they felt safe inside it,” he said.

When a cease-fire was announced, they went to their factory. “We were in shock,” he said. “The destruction was complete. Not only tanks. They brought bulldozers to finish the job.”

Avi Segal, an authority in security studies at Ben-Gurion University in Israel, expressed surprise that many factories were hit.

“The goal of the Israeli bombs is to cause pain, to bleed, so to speak. But the question is who. In my opinion, it is possible this was meant to harm those people so that they would pressure Hamas,” Segal said, referring to Gaza’s factory owners.

Mohammed Al Telbani, owner of the largest industrial plant in Gaza, said his factory was hit by 40 shells over several days, until it was consumed by fire when tons of butter, plastic and fuel ignited.

Al Awda factory employed 450 workers and made ice cream, cookies and chips. Telbani walked to the third floor and pointed to where Israeli shells entered one side and exited the other. The smell was enough to make him gag.

He denied that hostile fire came from his shop. “I never allow anyone near us. Not within a kilometer. My life is the factory. I live inside. I go to sleep at night listening to my production lines,” Telbani said. “There is no one like me in Gaza.”

“I was a symbolic target,” he said.

Like prominent business people in Gaza, Telbani is a “trusted traveler,” with permits to come and go through Israel and maintain close trading relations with Israeli counterparts.

Telbani denounced what he saw as the recklessness of the war. He said Israel is wrong to believe that business owners can sway Hamas to change course when the Arab League and Palestinian Authority have not been able to do so.

“Ask the Israelis what Mohammed Al Telbani ever did to them,” he said. “You say there were rockets fired from my cookie factory?” He was shaking with anger. “Prove it.”

Riham Abdul Karim in Gaza and Orly Halpern in Jerusalem contributed to this report.