Two suspected insurgents believed to be responsible for the death of Sgt. Deyson K. Cariaga, the first Hawai'i citizen-soldier to be killed in Iraq, have been captured and are in custody, the National Guard said.

The capture fulfills at least part of a promise made by fellow soldiers to find those responsible for the July 8 roadside bombing.

"I can't give you any specifics, but what I can tell you is that they belong to a cell that's been conducting indirect fire and IED (improvised explosive device) attacks on coalition forces," said 2nd Lt. Casey Miyamoto in a telephone interview from Logistical Support Area Anaconda in Iraq.

Miyamoto — with the 229th Military Intelligence Company, as was Cariaga — said "human" intelligence led to "target folders" being developed on the two Iraqis captured.

Both men, in their 30s, lived and operated in the area of Anaconda, he said.

Members of the 100th Battalion, 442nd Infantry, a U.S. Army Reserve unit attached to the Guard's 29th Brigade Combat Team, captured one of the men in a raid on his home. The 100th-442nd is responsible for an area of farmland and villages crisscrossed by Tigris River canals.

The man was caught by surprise and no shots were fired, Miyamoto said. The suspect remains in U.S. custody and is being processed through the U.S. system.

The other suspected insurgent, also wanted on a number of criminal warrants, was picked up by Iraqi police and is being prosecuted through the Iraqi judicial system.

Miyamoto said U.S. forces are not sure of the insurgent group's size.

He also couldn't reveal the total number believed to have been involved in Cariaga's death, but he said at least two have been captured.

"What we do know is that these guys are prominent insurgents," said Miyamoto, 25, of Pearl City. "Our higher headquarters in Baghdad — they heard about it and realized it was a big catch, too."

The captures are a boost for Hawai'i National Guard and Reserve soldiers about eight months into a yearlong deployment at LSA Anaconda north of Baghdad, and an example of some of the police-like investigations that go on day in and day out in Iraq to counter militants.

In a statement released yesterday, Theresa Inouye, Cariaga's mother, said she would like to thank the soldiers "who worked so hard to identify and capture those responsible for my son's death."

She also said in an e-mail: "We have great hope that justice will be served, and that those captured will never again be able to hurt anyone."

Just months after her son was killed and his ashes were interred at Punchbowl, in the National Memorial Cemetery of the Pacific, Inouye also asked that the people of Hawai'i not entertain thoughts of vengeance or hatred.

"We ask instead that they focus on praying for the safe return of those who continue to serve our country in Iraq," she said.

When Cariaga was killed, fellow soldiers vowed they would catch those responsible.

The 20-year-old Kalihi man's picture hangs prominently in the Joint Intelligence Center at LSA Anaconda, a poignant reminder for Hawai'i soldiers of the personal and overall importance of their mission when they track insurgents.

The 2002 Roosevelt High School graduate was the first of Hawai'i's citizen-soldiers to be killed on the deployment. Approximately 2,200 soldiers from the state are in Iraq and Kuwait.

Staff Sgt. Frank F. Tiai, 45, an American Samoan soldier serving with the 100th-442nd, was killed by a roadside bomb nine days later near LSA Anaconda.

Cariaga was working in intelligence with Air Force counterparts and was driving the third of seven Humvees back to base when a 155 mm artillery round exploded practically beneath him on an asphalt road that the military calls Route Heather.

Three agents of the Air Force Office of Special Investigation stumbled out of the Humvee, which caught fire. Cariaga bore the brunt of the blast. His company commander said that if the explosion were 18 inches to the rear, everyone might have been killed.

Miyamoto, who joined the Hawai'i soldiers in Iraq in May after being commissioned a second lieutenant and going through additional training, remembers having lunch with Sgt. Cariaga the day when the second lieutenant arrived at LSA Anaconda. Cariaga met with Iraqis as an intelligence gatherer and was a combat lifesaver, a step below medic.

"He was a very funny guy and he had the biggest smile I've ever seen on a person," Miyamoto said by phone. His death was "devastating," but it "made us more determined to do our jobs, and now our hard work is paying off in finding these guys who were responsible for his death."

Miyamoto said the human intelligence analysis unit that he heads tracks more than 1,900 insurgents. Enemy activity remains high in the area, and Hawai'i soldiers encounter multiple roadside bombs daily — many of which are discovered before they are detonated.

Counterinsurgency intelligence works on multiple layers and includes tactical human intelligence teams like the one Cariaga was part of; the analysis cell, which disseminates information to ground units like the 100th-442nd; and agents from the Air Force Office of Special Investigation.

Maj. Moses Kaoiwi, 39, assistant intelligence officer for the Hawai'i brigade at LSA Anaconda and a one-time police detective on the Big Island, said in July that a lot of intelligence work "has to do with contacting people and getting information, basically like a police officer gets information on the street."

An insurgent also may be a farmer or a taxi driver. Soldiers on patrols routinely ask villagers if there are any "bad guys" around, and informants are widely used, although such information often leads U.S. troops on wild goose chases.

"It's like having a whole bunch of arrest warrants and going out and looking for the people," Kaoiwi said.

Reach William Cole at wcole@honoluluadvertiser.com.