Security analysts say the armed uprising in Libya poses a long-term security threat — that weapons looted from government stockpiles could circulate widely, including heat-seeking antiaircraft missiles that could be used against civilian airliners.
Past examples of state arsenals being looted by civilians — whether in Uganda in 1979, Albania in 1997 or Iraq in 2003 — have shown that once these weapons slip from state custody they can be sold through black markets, swiftly and quietly, to other countries and groups for use in wars where they can present long-lasting and destabilizing problems. Analysts are particularly concerned about the heat-seeking missiles, known as Man-Portable Air-Defense Systems, or Manpads.
Col. Muammar el-Qaddafi's military was not particularly well-led, competent or large at the start of this conflict, with an army of roughly 45,000 soldiers, according to an assessment by Jane's Information Group.
But over the decades, Colonel Qaddafi has spent heavily to equip his forces and amass reserve munitions and arms. He has been accused of procuring weapons to pass on to many foreign groups, including Palestinian and Irish fighters, rebel groups and friendly governments in sub-Saharan Africa.
Mixed in are rifles of Romanian, Hungarian and Russian provenance, along with crates of ammunition from Norinco, one of the principal arms-manufacturers in China.
Nic Marsh, who researches the small-arms trade for the Peace Research Institute Oslo in Norway, said the weapons could move in many directions, to Chad or Sudan, to Algeria or to Palestinian fighters.
If the battles in Libya turn into a long war, the two sides might actually import more weapons to sustain their fighting. But once the uprising is resolved, if history is a guide, the weapons stand to be sold off piece by piece.
In these cases, as in Albania in the late 1990s, weapons become commodities, and organized smuggling rings can swiftly form to move them on.
Assault rifles in Africa often fetch several hundred dollars apiece. The weapons now circulating in Libya, fresh from arsenals and evidently in good condition, could be worth more — creating an incentive for those who hold them now to dump them onto markets later.
The Manpads, analysts said, are much more difficult to acquire and would command significantly higher prices and attract their own subset of buyers. "When the guys outside the country realize that there are Manpads available, they will try to get them," Mr. Danssaert said. By "guys," he said, he meant terrorist organizations.
The precise sources and types of the missiles that the rebels have lifted from stockpiles are not fully clear, and the sample of images remains small.
But photographs by The New York Times clearly show SA-7 missiles, apparently of the so-called SA-7b, an improvement on the original design, Mr. Schroeder said. One image, of the stenciled markings on a launch tube, shows a missile that appears to have been manufactured in November 1977.
The SA-7, an early-model missile, was fielded in the Soviet Union in the late 1960s for use against NATO military planes. There have been multiple manufacturers of SA-7b knockoffs outside the former Soviet Union, including in Egypt, Pakistan, Bulgaria and China.
Carried and fired by a single fighter, the missiles travel at supersonic speeds from a shoulder-fired launcher toward the heat emitted by an aircraft engine, where they detonate a high-explosive charge.
Many modern military planes use countermeasures to confuse such weapons. But very few civilian aircraft do.
Analysts fear that now that these weapons are out of state hands, they will be more easily acquired by groups that could use them against civilian jets, as terrorists did in Mombasa, Kenya, in 2002, when two missiles narrowly missed an Israeli plane with 271 people aboard.
There have been numerous other attacks against aircraft, many of which have been destroyed in flight.
Some of the attacks were devastating: an Air Rhodesia plane was downed by an SA-7 in 1979, killing all 59 people aboard; an American-supported guerrilla group claimed that it downed a Boeing 737 flown by Angolan Airways with a missile in 1983, killing 130 people; the Sudanese People's Liberation Army used an SA-7 to destroy a Sudan Airways passenger plane in 1986, killing 60 people.
In 1994, a plane carrying the presidents of Burundi and Rwanda was struck by a Manpads, killing both men and setting off genocide in Rwanda.
Even Manpads that are not fired, or miss their targets, can cause economic ripples, because aviation companies might be unwilling to service routes in areas where terrorist groups are believed to possess them. "A perceived threat can have an effect," said Eric Berman, managing director of the Small Arms Survey in Geneva, which has researched the missiles' proliferation.
In the popular imagination, heat-seeking surface-to-air missiles are simple to use and uncannily reliable, but many of them are far from fail-safe.
Most of the missile systems require a degree of training to assemble and fire them effectively, including a sense of the weapons' minimum and maximum ranges and the degree to which targets should be led.
Moreover, the weapons themselves can malfunction and degrade. The SA-7, for example, has three primary components, including a grip stock that holds the weapon, a battery-cooling unit that is necessary to arm and fire it, and a launch tube that contains the missile itself.
Some of the images from Libya show men carrying only partially assembled systems. Such weapons appear menacing to the passing eye, but unless fully assembled are harmless to passing aircraft.
And even when properly assembled and carried by competent users, other factors — such as how the missiles and batteries were stored, their age, and their provenance — influence whether they will work when fired. "You can have a lot of missiles out there, but many might not be effective," Mr. Berman said.
The analysts said that in the short term, little could be done about the loose weapons.
Mr. Berman expressed hope that the Libyan government had maintained detailed records of its weapons' serial numbers, so that after the conflict it would be possible to determine exactly what is missing, and then to organize programs to recover or account for the Manpads, one by one.
The United States government has been active in trying to account for and destroy the missile stockpiles, and underwrote buy-back programs that recovered many of the weapons that disappeared in 2003 from Saddam Hussein's storehouses in Iraq.