Israeli military and intelligence officials have concluded that a significant number of weapons used by Hamas in the October 7 attacks and in the war in Gaza came from an unlikely source: the Israeli military itself.
For years, analysts have pointed to underground smuggling routes to explain how Hamas remained so heavily armed despite Israel’s military blockade of the Gaza Strip. But recent intelligence has shown the extent to which Hamas has been able to build many of its rockets and anti-tank weapons from the thousands of munitions that failed to detonate when Israel launched them into Gaza, according to Israeli weapons and intelligence experts and Westerners. officials. Hamas is also arming its fighters with weapons stolen from Israeli military bases.
Intelligence gathered during months of fighting revealed that, just as Israeli authorities misjudged Hamas’s intentions before October 7, they also underestimated its ability to obtain weapons.
What is clear now is that the same weapons that Israeli forces have used to enforce the blockade of Gaza for the past 17 years are now being used against them. Israeli and US military explosives have allowed Hamas to launch rockets into Israel and, for the first time, penetrate Israeli cities from Gaza.
“Unexploded ordnance is the main source of explosives for Hamas,” said Michael Cardash, former deputy chief of the Bomb Disposal Division of the Israel National Police and a consultant to the Israeli police. “They are cutting open Israeli bombs, Israeli artillery bombs, and many of them, of course, are being used and reused for their explosives and rockets.”
Weapons experts say about 10 percent of munitions typically fail to detonate, but in Israel’s case, the figure could be higher. Israel’s arsenal includes Vietnam-era missiles, long discontinued by the United States and other military powers. The failure rate of some of those missiles could be as high as 15 percent, said an Israeli intelligence official who, like others interviewed for this article, spoke on condition of anonymity to discuss intelligence matters.
By either estimate, years of sporadic bombing and the recent bombing of Gaza have left thousands of tons of unexploded ordnance in the area waiting to be reused. A 750-pound bomb that does not detonate can become hundreds of missiles or rockets.
Hamas did not respond to messages seeking comment. The Israeli military said in a statement it was committed to dismantling Hamas but did not answer specific questions about the group’s weapons.
Israeli officials knew before the October attacks that Hamas might salvage some Israeli-made weapons, but the extent has surprised weapons experts and diplomats alike.
Israeli authorities also knew that their arsenals were vulnerable to theft. A military report early last year said thousands of bullets and hundreds of weapons and grenades had been stolen from poorly guarded bases.
From there, according to the report, some headed to the West Bank and others to Gaza via the Sinai. But the report focused on military security. The consequences were treated almost as an afterthought: “We are feeding our enemies with our own weapons,” read one line of the report, which was seen by The New York Times.
The consequences became evident on October 7. Hours after Hamas crossed the border, four Israeli soldiers discovered the body of a Hamas gunman who was killed outside the Re’im military base. A grenade he was carrying on his belt had Hebrew writing on it, said one of the soldiers, who recognized it as an Israeli bulletproof grenade, a recent model. Other Hamas fighters overran the base and Israeli military officials say some weapons were looted and returned to Gaza.
A few kilometers away, members of an Israeli forensic team collected one of the 5,000 rockets launched by Hamas that day. Examining the rocket, they discovered that its military-grade explosives likely came from an unexploded Israeli missile fired at Gaza during a previous war, according to an Israeli intelligence official.
The October 7 attacks showed the arsenal of mosaics that Hamas had put together. It included Iranian-made attack drones and North Korean-made rocket launchers, the type of weapons Hamas is known to smuggle into Gaza through tunnels. Iran remains a major source of Hamas’ money and weapons.
But other weapons, such as anti-tank explosives, RPG warheads, thermobaric grenades and improvised devices, were reused Israeli weapons, according to Hamas videos and remains discovered by Israel.
The rockets and missiles require huge quantities of explosive material, which officials say is the most difficult item to smuggle into Gaza.
However, Hamas fired so many rockets and missiles on October 7 that Israel’s Iron Dome air defense system could not keep pace. The rockets hit towns, cities and military bases, providing cover for militants who broke into Israel. A rocket hit a military base believed to house part of Israel’s nuclear missile program.
Hamas once relied on materials like fertilizer and powdered sugar (which, pound for pound, are not as powerful as military-grade explosives) to build rockets. But since 2007, Israel has imposed a strict blockade, restricting the import of goods, including electronic and computer equipment, that could be used to make weapons.
That blockade and the crackdown on smuggling tunnels in and out of Gaza forced Hamas to get creative.
Its manufacturing capabilities are now sophisticated enough to cut off the warheads of bombs weighing up to 2,000 pounds, collect the explosives and reuse them.
“They have a military industry in Gaza. Some of it is above ground, some of it is underground, and they can make a lot of what they need,” said Eyal Hulata, who served as Israel’s national security adviser and head of its National Security Council before resigning early. last year.
A Western military official said most of the explosives Hamas is using in its war with Israel appear to have been made from unexploded ordnance dropped by Israel. An example, the official said, was an explosive trap who killed 10 Israeli soldiers in December.
Hamas’s military wing, the Qassam Brigades, has boasted of its manufacturing capabilities for years. After a 2014 war with Israel, it established teams of engineers to collect unexploded ordnance, such as howitzers and American-made MK-84 bombs.
These teams work with police explosive ordnance disposal units, allowing people to safely return to their homes. They also help Hamas prepare for the next war.
“Our strategy aimed to reuse these parts, turning this crisis into an opportunity,” a Qassam Brigades commander told Al Jazeera in 2020.
Qassam’s media arm has released videos in recent years showing exactly what they were doing: cutting off warheads, extracting explosive material (usually a powder) and melting it down for reuse.
In 2019, Qassam commandos discovered hundreds of munitions on two British World War I warships that had sunk off the coast of Gaza a century earlier. The discovery, Qassam boasted, allowed him to make hundreds of new rockets.
Early in the current war, a Qassam video showed Militants assembling Yassin 105 rockets in a sunless manufacturing facility.
“The most essential way for Hamas to obtain weaponry is through domestic manufacturing,” said Ahmed Fouad Alkhatib, a Middle East policy analyst who grew up in Gaza. “It’s just a touch of chemistry and you can pretty much do whatever you want.”
Israel restricts the mass import of construction materials that can be used to make rockets and other weapons. But each new round of fighting leaves behind neighborhoods littered with rubble from which militants can rip out pipes, concrete and other valuable materials, Alkhatib said.
Hamas cannot manufacture everything. Some things are easier to buy on the black market and smuggle into Gaza. The Sinai, the largely uninhabited desert region between Israel, Egypt and the Gaza Strip, remains a hub for arms smuggling. According to Israeli intelligence assessments, weapons from the conflicts in Libya, Eritrea and Afghanistan have been discovered in the Sinai.
According to two Israeli intelligence officials, at least a dozen small tunnels still existed between Gaza and Egypt before October 7. An Egyptian government spokesman said his army had done its part to close the tunnels on its side of the border. “Many of the weapons currently located inside the Gaza Strip are the result of smuggling from within Israel,” the spokesperson said in an email.
But the besieged streets of Gaza itself are increasingly a source of weapons.
Israel estimates it has carried out at least 22,000 strikes in Gaza since October 7. Each often involves multiple rounds, meaning tens of thousands of munitions have likely been launched or fired, with thousands failing to detonate.
“Artillery, hand grenades, other munitions – tens of thousands of unexploded ordnance will remain after this war,” said Charles Birch, head of the U.N. Mine Action Service in Gaza. These “are like a free gift to Hamas.”
Vivian Yee contributed reporting from Cairo and Zakaria Zakaria from Rotterdam, Netherlands.