BAGHDAD — U.S. troops stationed at an outpost in southern Iraq heard a chilling whistle, and then a 60-pound airborne bomb punched through a concrete blast wall and sent shrapnel flying, wounding three Americans.
Explosions are commonplace in Iraq, but this was no ordinary attack. The U.S. military said Friday that militants who launched the Jan. 12 attack on a joint U.S.-Iraqi compound used an unusual weapon called an IRAM, for Improvised Rocket-Assisted Munition. Sometimes called "flying IEDs," IRAMs are a potentially deadlier incarnation of the garden-variety Improvised Explosive Devices in Iraq and Afghanistan — they're short-range projectiles that catapult toward unsuspecting targets.
Two IRAMs flew into the outpost in the city of Amarah in a puzzling reappearance of a weapon that's been used only 14 times since the U.S. invaded Iraq in 2003, according to the U.S. military. Most of the earlier attacks occurred in eastern Baghdad more than 18 months ago, at the height of violence related to Shiite Muslim militias. The more recent attacks, however, were launched in southern Iraq's Maysan Province, which borders Iran.
In the most recent incident, only one of the IRAMs exploded, leaving a 12-foot crater in the ground, said Maj. Myles Caggins, a spokesman for the 4th Brigade of the Army's 1st Armored Division, which is based in Fort Bliss, Texas, and is operating in Maysan.
The other was a dud that's now being investigated by American and Iraqi forensics teams to determine its components and origins. Previous IRAMs have been linked to the Mahdi Army of volatile Shiite cleric Moqtada al Sadr and other Iranian-backed militias in Iraq.
"Violent Shiite extremist groups typically receive influence from Iranian origins," Caggins said, noting that so far there's no direct evidence that ties the latest attack to Iran. "The Iraqi police we advise are aggressively seeking to root out these networks of terrorists, smugglers and financiers who import and assemble these weapons."
In June 2008, the Long War Journal, an online publication about counterterrorism issues, reported that what most media had referred to as a car bomb that killed at least 16 people and wounded 29 in eastern Baghdad that month was actually a premature detonation of an IRAM. The report said the IRAMs were "of Iranian manufacture" and were propelled by 107mm rocket charges.
The Washington Post reported in July 2008 on a flurry of rocket-propelled bomb attacks on U.S. installations in eastern Baghdad, also quoting military sources who said that Iranian-backed militias were responsible for the weapons. One system that failed to ignite included nine IRAMs, each packed with 200 pounds of explosives, the Post reported.
Details about the latest attack are classified pending a U.S. military investigation, and there's still little awareness of IRAMs, even among U.S. soldiers.
"I'd never heard of it — not before it blew up on us," said Spc. Robert B. Walsh, 27, of Venice, Fla., who survived an IRAM blast last summer at the same place as the latest attack.
The military awarded Purple Hearts to Walsh and two other wounded soldiers from the Army's Charlie Company, 4th Battalion, 6th Infantry Regiment. Theirs was the last confirmed IRAM incident in Maysan — and possibly in Iraq — before the ones this week.
Walsh, who's still in Iraq, said he was on duty in a guard tower on the American side of the joint outpost at 6 a.m. last June 30, which was supposed to have been a day of celebration as the new U.S.-Iraqi security pact took effect.
"I guess they wanted the last little hurrah," Walsh said.
Four men in two trucks pulled into a gas station next to the base. As passengers in the first truck filled their tank, the other men parked the second truck and jumped into the first vehicle. They drove away, Walsh said, leaving behind the second truck loaded with as many as three IRAMs set to a timer.
Walsh said his only clue before the blast was "a poof sound." In the seconds before impact, Walsh used his radio to alert other soldiers to possible incoming fire.
The IRAM zipped over the wall "like a big bottle rocket," Walsh said. It passed his guard tower and blew up next to a kitchen and barracks where American troops were sleeping.
The other two Purple Heart recipients received shrapnel wounds when windows and doors blew into their quarters, cutting their faces and hands. Several vehicles were damaged or destroyed, and the force of the explosion cracked the foundation and shifted the roof of the concrete building.
"It threw me about three or four feet and knocked me unconscious," Walsh said. "When I woke up, everything was on fire and there was debris all over the ground. It left a hole with a 15-foot radius, and it was 4 1/2 feet deep."
Still, Walsh considers himself fortunate. There were at least two others IRAMs in the truck, he said, but the blast from the first one knocked others off their railing and burned out the ignition wire.
"Only one of them had gone airborne," Walsh said. "We were lucky, I guess, if you look at it that way."
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