“It’s a big breakthrough,” said Paul F. Walker, an arms control expert with the environmental group Green Cross International who has helped in efforts to demilitarize the American and Russian chemical weapons stockpiles since the 1990s. “Even though Libya’s chemical stockpile was relatively small, the effort to destroy it was very difficult because of weather, geography and because it’s a dangerous area with warring tribes, increasing the risks of theft and diversion,” he said. 
 
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 Libya’s last two tons of chemical weapons were dwarfed by the 1,300 tons that Syria has agreed to destroy. But American and international arms experts say the need for easily transportable and efficient technology to wipe out the Libyan arms became a model for the Syria program now underway. 
 
 For Libya’s fragile transitional government, such collaboration with the West on security matters is a delicate issue. It gives the country’s leaders desperately needed assistance to defuse internal threats, but also risks accusations of compromising national sovereignty. 
 
 Asked about the American efforts to destroy the chemical weapons, Libyan security officials in Tripoli initially issued sweeping denials. One later briefly acknowledged the operation on the condition of anonymity, and then officials stopped returning phone calls. 
 
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 On Sunday, the White House said that it would ensure that the Syrian government complied with an accord to give up its chemical arsenal despite missed deadlines and delays in carrying out the deal. 
 
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 The White House chief of staff, Denis McDonough, said on the CBS News program “Face the Nation” that the deal was “not falling apart, but we would like to see it proceed much more quickly than it is.” 
 
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 The disposal of the last of Libya’s chemical weapons closes a chapter that Colonel Qaddafi began in early 2004, when his government turned over a vast cache of nuclear technology and chemical stockpiles to the United States, Britain and international nuclear inspectors. 
 
 At that time, Libya declared for destruction 24.7 metric tons of sulfur mustard, a syrupy liquid that when loaded into bombs or artillery shells and exploded creates a toxic mist that penetrates clothing, burns and blisters exposed skin, and can kill with large doses or if left untreated. The chemical was used extensively in World War I. 
 
 Libya had destroyed about half of these stocks when civil war broke out in 2011. Western spy agencies closely monitored the destruction site in the Libyan desert to ensure the stockpiles were not pilfered by insurgents. 
 
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 When the new government took control in Tripoli that fall, it signaled its intent to finish the job. Libyan officials also surprised Western inspectors by announcing the discovery in November 2011 and February 2012 of two hidden caches of mustard, or nearly two tons, that had not been declared by Colonel Qaddafi’s government. That brought the total declared amount of chemical to 26.3 tons. 
 
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 Unlike the majority of Libya’s mustard agents, which were stored in large, bulky containers, the new caches were already armed and loaded into 517 artillery shells, 45 plastic sleeves for rocket launchings and eight 500-pound bombs. 
 
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 The new stockpiles immediately posed huge challenges for the fledgling Libyan government, which had no ability to destroy the combat-ready chemical weapons, as well as for its American and European allies called upon to help. 
 
 The disposal site is deep in the desert, in an area where Islamist militants hostile to the West wield growing influence. It also sits on the front line of the struggle between Libya’s eastern and western provinces over political power and oil revenue. A defining issue in post-Qaddafi politics, the regional rivalry has often spilled out into armed blockades of the national highways and crucial oil-export terminals as well. 
 
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 Using $45 million from the Nunn-Lugar Cooperative Threat Reduction program, which has helped rid the former Soviet Union of thousands of nuclear weapons since the end of the Cold War, the Pentagon and its Defense Threat Reduction Agency tapped the Parsons Corporation, a construction firm based in Pasadena, Calif., to work with Libya to oversee the rebuilding and safeguarding of the Libyan disposal site, which had been ransacked during the civil war. 
 
 Remarkably, the mustard agents stored in bulk containers at the site were untouched and their inspection seals unbroken, American and international officials said. These have all been destroyed, too. 
 
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 Canada donated $6 million to help restore water, sewage service and electricity to the site, and to build living quarters for Western and Libyan contractors. Germany agreed to fly international inspectors to the site. 
 
 The project has relied on a custom-built device from Dynasafe, a Swedish company, to destroy the weapons. It is essentially a giant, high-tech oven called a static-detonation chamber. The munitions were fed through an automated loading system into a gas-tight chamber, where the toxic materials were vaporized at temperatures between 750 and 1,000 degrees Fahrenheit. Gases created in the process were scrubbed by special filters. 
 
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 “The destruction of these munitions was a major undertaking in arduous, technically challenging circumstances,” Ahmet Uzumcu, the director general of the Organization for the Prohibition of Chemical Weapons, whose inspectors supervised the destruction of the chemical weapons, said in a written statement. 
 
 Although American officials acknowledge that Libya is awash with conventional arms, they expressed confidence that the vast Libyan desert holds no other secret caches of unconventional arms for jihadis to exploit. 
 
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 Andrew C. Weber, assistant secretary of defense for nuclear, chemical and biological defense programs, said, “This is the culmination of a major international effort to eliminate weapons of mass destruction from Libya and to ensure that they never fall into the hands of terrorists.” ||||| WASHINGTON — It may be possible for the United Nations to disarm Syria of its chemical weapons, but the complex operation probably would require years to complete and would be extraordinarily difficult while much of the country is consumed by civil war. 
 
 As the White House and its allies moved closer Tuesday to seeking U.N. support for a Russian proposal to collect and destroy Syrian President Bashar Assad's vast arsenals of toxic weapons, veteran inspectors and other experts began to focus on the technical and logistic challenges such a plan would entail. 
 
 The biggest question is whether Syria would disclose its clandestine procurement systems, development and production infrastructure, chemical supplies, weapons stores, armed delivery systems, command-and-control networks and other details necessary to verify compliance. 
 
 "The Syrians would have to tell us basically everything, and they'd also have to confess to using chemical weapons, which they may be reluctant to do" because it could make commanders vulnerable to charges of war crimes, said Markus Binder, a chemical weapons expert at the University of Maryland. 
 
 Assad's government also presumably would need to grant international weapons inspectors unfettered access to now-secret chemical weapons facilities and other sensitive systems controlled by the ruling elite. 
 
 Sen. Dianne Feinstein (D-Calif.), who chairs the Senate Intelligence Committee, said inspectors probably would seek to transfer weapons and materials from about 40 known facilities to a few neutral sites, either in Syria or a nearby country, so they could disable or destroy them. 
 
 "There would have to be consolidation of these sites," she said. 
 
 The inspectors almost certainly would require armed security while Assad's army grapples with a rebellion in much of the country. Some experts worry that extremist groups or other insurgents would target the inspection teams and try to seize or use the weapons. 
 
 "In Syria we have militants that may want to sabotage the whole thing," said Raymond Zilinskas, a nonproliferation expert at the Monterey Institute of International Studies. "You would need security, and is that going to be an international force or will they depend on the Syrian army? There are all kinds of details that have to be worked out. I don't think it's going to happen very quickly." 
 
 "There are two risks: the risk of the war coming to the weapons, in the form of getting caught in crossfire or attacked specifically, and the risk of the munitions themselves leaking," said Tim Trevan, who worked with the U.N. teams that sought to disarm Iraq of chemical, biological and nuclear weapons after the 1991 Persian Gulf War. 
 
 Appearing before the House Armed Services Committee, Secretary of State John F. Kerry said Syria's military had about 1,000 metric tons of chemical agents, including mustard gas, which causes horrific burns, and VX and sarin, which affect the nervous system. 
 
 Most of the sarin and VX are kept as precursor chemicals that may be mixed to form the deadly neurotoxin. Syria also possesses small rockets, artillery shells and other munitions pre-loaded with sarin. 
 
 The Obama administration says Assad's forces fired dozens of small rockets loaded with sarin into rebel-held neighborhoods east of Damascus on Aug. 21, killing more than 1,400 people. Assad's government has denied it. 
 
 Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, told the Senate committee that Syrian forces had moved their chemical weapons to bases under their control. That might make it easier to protect visiting U.N. inspectors, as well as ultimately to remove or destroy the munitions. 
 
 Lethal chemicals can be burned in special high-temperature incinerators, or combined with other compounds to render them inert. Doing either requires special handling and carries considerable risk of leakage or contamination. Some munitions may be so unstable that they are stored in airtight bunkers. 
 
 Inspectors might seek to fly some of the toxic materials and munitions out of Syria. In 2004, in a then-secret deal with Libyan ruler Moammar Kadafi, U.S. and British officials secretly dismantled Libya's nascent nuclear weapons program and flew key components and supplies to the Oak Ridge National Laboratory in Tennessee. 
 
 Dismantling Libya's stockpile of mustard gas, a blister agent made infamous in World War I, proved more difficult, however. 
 
 The 23 tons of toxic mustard was stored in 1-liter plastic jugs in padlocked warehouses. The containers were deemed too dangerous to move, said Donald Mahley, who oversaw the effort to dismantle Libya's nuclear and chemical programs. 
 
 He said Libyan officials agreed to move the mustard to a military base that U.S. satellites could surveil, and plans were made to build a special incinerator nearby. The U.S. also destroyed the bombs built to deliver the mustard, Mahley said. 
 
 In May, the Organization for the Prohibition of Chemical Weapons, an international body based in The Hague that monitors compliance with the Chemical Weapons Convention, announced that Libya had destroyed 85% of its mustard, more than a decade after declaring it. 
 
 The inspection and verification process is far from foolproof. In Iraq, Saddam Hussein's government offered a continually shifting list of weapons, facilities and personnel, leading to a complete breakdown of credibility with the outside world. 
 
 "In Iraq, they couldn't explain to our satisfaction what had happened to several tons of material that their records say they had produced," said Joseph Cirincione, president of the Ploughshares Fund, which works on nonproliferation issues. "They said it had been destroyed in the desert. We didn't believe them. It turned out that it was true." 
 
 The U.S. learned only after it invaded Iraq in 2003 to find and destroy Hussein's weapons of mass destruction that they no longer existed. 
 
 ken.dilanian@latimes.com 
 
 shashank.bengali@latimes.com
– The destruction of Syria's chemical weapons continues to hit delays—but a secret effort to rid Libya of chemical weapons has been a success, the New York Times reports. The US and Libya have been destroying what was left of Moammar Gadhafi's stockpile, including hundreds of weapons containing a mustard agent. The three-month project, which wiped out two tons of arms using what the Times calls a "giant, high-tech oven," ended last week. "It’s a big breakthrough," says an expert, noting that the process—a basis for the much larger effort in Syria—"was very difficult because of weather, geography, and because it's a dangerous area with warring tribes, increasing the risks of theft and diversion." In 2004, Gadhafi had provided some 24.7 metric tons of chemical weapons to the West for destruction, but only half were gone by the time civil war began in 2011. The post-Gadhafi Libyan government sought to rid itself of the remainder, as well as almost two tons of additional material it had found—agents already installed in bombs and artillery, the Times notes. The destruction effort, which used funds from the Pentagon as well as Canada, saw the weapons vaporized in an oven created by Swedish firm Dynasafe. Meanwhile, the BBC is airing old Gadhafi secrets in a special tonight; among them, a former ally who says the strongman ordered a plane shot down near Tripoli in 1992, killing 157 passengers in a demonstration against sanctions.