Deadly Triggers

Why is the Bush administration escalating its accusations that Iran is backing Shiite extremists inside Iraq? One reason: mounting intelligence indicating Tehran has been supplying insurgents with electronic sensors that trigger roadside bombs used against U.S. troops.

The devices in question—which cost as little as $1 a piece—are called "passive infrared" sensors or detectors. They are commonly used to turn on lights or burglar alarms when someone or something passes in front of them. Over the past year, U.S. forces in Iraq have repeatedly fallen victim to sophisticated homemade bombs—known as “IEDs”, or improvised explosive devices—which are often rigged with passive infrared sensors.

Recent reports from U.S. intelligence agencies show that Iranian agents or brokers have ordered the devices in bulk from manufacturers in the Far East, said one U.S. counter-terrorism official, who asked not to be identified discussing sensitive matters. Bruce Riedel, a senior intelligence official who retired from the CIA only two months ago, told Newsweek he too was aware of reports that serial numbers of sensors retrieved from IEDs in Iraq have been traced to orders from Iran placed with infrared-sensor manufacturers in Taiwan and Japan. (Riedel is now an analyst with the Saban Center at the Brookings Institution).

The infrared devices are particularly deadly as triggers for home-made bombs. Unlike cellphones, radio control systems or garage-door openers—some of the other devices which have been used by Iraqi insurgents to trigger IEDs—the infrared devices do not emit a signal that can be detected before they go off. As a result, it is particularly difficult for U.S. forces to locate and defuse IEDs rigged with such triggers.

The presence of the infrared sensors is not the only intelligence pointing to an Iranian role in the construction of IEDs. Some recovered bombs closely match IED designs known to have been used by the Lebanese Shiite movement Hizbollah—another group that relies heavily on Iranian arms and money. A current counter-terrorism official says that bomb-making videos believed to have been prepared in Iran have been recovered from insurgents in Iraq. Similar or identical tutorials have also been recovered from Hizbollah, the counter-terrorism official said. The video discs contain instructions on how to build homemade bombs with “shaped charges” (known in military jargon as EFPs, or "explosive formed projectiles")—particularly deadly devices capable of penetrating tank armor. These, too, are known to have been used by Hizbollah.

U.S. officials say they believe the supply of equipment and components to insurgents inside Iraq is being arranged in Iran by the Al-Quds brigades. This group is an offshoot of the Islamic Revolutionary Guards Corps, a national militia organization charged with protecting Iran’s theocratic government from counter-revolutionary forces. The Corps is believed to operate under the direct authority of Iran’s outspoken and controversial president, Mahmoud Ahmadinejad, who himself originally rose to prominence as a member of the organization.

Christine DeVries, a spokeswoman for a special Defense Department task force assigned to track IEDs in Iraq, declined to talk about any intelligence linking IEDs to Iran. She said the task force never speaks in public about “what we’re seeing the enemy do,” though she added that U.S. forces are dealing with “an adaptive enemy, who uses everything at his disposal.”

In recent weeks, the Bush administration, along with the government of British Prime Minister Tony Blair, has made increasingly dramatic assertions about Iranian interference in Iraq—alleging the existence of a pipeline that flows between Iran and Shia extremists who have been implicated in attacks on U.S. troops. In testimony last week before the Senate Intelligence Committee, CIA Director Michael Hayden focused in particular on the presence of the explosive formed projectiles. "They are being used against our forces. They are capable of defeating some of our heaviest armor, and incident for incident cause significantly more casualties than any other improvised explosive devices do, and they are provided to Shi'a militia."

But officials have not publicly discussed the link between Iran's purchase of infrared sensors and the use of the sensors in the assembly of roadside bombs in Iraq—a connection that potentially makes the administration's allegations stronger. Current and former intelligence officials also cautioned that Iranian involvement in the insurgency should not be overstated. They noted, for example, that most IED attacks on U.S. forces in Iraq are launched by Sunni insurgents, rather than the Shia elements most directly backed by Iran.

One senior U.S. intelligence official, speaking recently to a group of reporters on condition of anonymity, acknowledged that only a “small percentage”" of IEDs found in Iraq show signs of possible Iranian origin, though the official indicated that because of their more sophisticated design, the Iranian-linked IEDs tend to be more deadly than Sunni home-made bombs.

Some congressional Democrats have also expressed concern that the administration was overstating the Iranian connection in the same way that Bush and his aides did in the run-up to the US invasion of Iraq. Through a spokesman, the new chairman of the House Intelligence Committee, Rep Silvestre Reyes, told Newsweek that he intended to look into the intelligence behind administration claims about Iranian IED supplies. “Senior administration officials, including the president himself, have said publicly that Iran has sent IEDs into Iraq,” Reyes said, adding: “I will be closely examining the intelligence that underlies those claims.”

Nevertheless, intelligence officials contacted by Newsweek insist that Iranian interference in Iraq appears significant. U.S. intelligence officials say they are aware of staging points—sometimes upgraded in unofficial accounts to "training camps"—in Iran, Syria and Lebanon that are used by insurgents traveling in and out of Iraq. Intelligence agencies believe that supplies, such as the sensors, are shipped from these locations.

One U.S. official said that the staging posts do not necessarily stay in the same location for long, which would greatly complicate any efforts by U.S. secret military units or intelligence teams to shut them down. Another U.S. official said that information about one such staging area in Syria is well-known. But the details about what goes on there—and information about the extent to which civilians are present at the site—are murky. Any U.S. move against them could cause unwanted civilian casualties and a major confrontation with Syria.

U.S. officials believe supplies and personnel are moved across the Iraqi border from Iran via “ratlines”—intelligence jargon for smuggling routes—which, in some cases, are fairly well-documented by intelligence reporting. However, those same routes are also used by large numbers of Iranian pilgrims who travel to and from sacred Shia shrines inside Iraq. This can make it difficult, if not impossible, for U.S. forces to crack down on Iranian aid to insurgents because it is impossible to tell pilgrims from Iranian government operatives.

U.S. officials note that all the major Iraqi Shiite parties, including Prime Minister Nouri al-Maliki’s, have strong historical ties to Iran; some of the groups even operated from Tehran during Saddam Hussein's dictatorship. An Iranian outpost in the Kurdish town of Erbil which was recently the target of a controversial U.S. military raid has been known for the last 10 years as an Iranian intelligence base, a former official said. And one of the biggest open secrets in Iraq is the identity of the station chief of Iranian intelligence. According to former CIA official Riedel, he is one of the “most important figures in Baghdad.” But this person operates from the Iranian Embassy, almost certainly under cover of diplomatic immunity. While his identity is known to intelligence agencies and his activities may be watched, there is little if anything—short of a violation of diplomatic conventions that could amount to an act of war—that U.S. forces can do to shut him down.

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