Saudi fighters make up only about 1 percent of Iraq's insurgency, but each contributes thousands of dollars to the cause — and they make sure their roles as "martyrs" are known when they carry out suicide attacks, helping draw more recruits, a new report said.

About 30,000 fighters are believed to be involved in the insurgency, approximately 90 percent of them Sunni Arab (search) Iraqis motivated by fear of Shiite (search) domination or anger over lost power, said the report by the Washington-based Center for Strategic and International Studies.

Of the estimated 3,000 foreign fighters, the largest number — about 20 percent — comes from Algeria, followed by Syria and Yemen with about 18 percent and 17 percent, respectively, said the report issued Monday. About 15 percent come from Sudan, 5 percent from Egypt, and 5 percent from other countries.

Of about 350 Saudis who entered Iraq by August 2005, about 130 are believed to have been killed or captured, it said.

The report, written by Nawaf Obaid and Anthony Cordesman, was a contrast to accounts contending that Saudis make up a large proportion of foreign fighters in the insurgency that has persisted since the fall of Saddam Hussein's regime in March 2003.

The study by the CSIS, an independent think tank, said its information was compiled from estimates provided by Saudi intelligence services based on interrogations of captured militants and other sources, and by intelligence agencies of other, unidentified governments in the region.

The "main pillar" of the insurgency is not former Saddam loyalists, though they do contribute expertise, the report said. Instead the bulk of fighters are members of Sunni Arab Iraqi tribes. "Although they do not support a return to Saddam Hussein's regime, most are Sunnis wary of a Shiite-led government," it said.

Most of the Saudis who join the insurgency "were motivated by revulsion at the idea of an Arab land being occupied by a non-Arab country" and anger over allegations of U.S. abuses at the Abu Ghraib (search) or Guantanamo Bay (search) prisons, it said. They average in age between 17-25.

Notably, most of those caught by Saudi authorities trying to enter Iraq "were not militants before the Iraq war," it said. Eighty-five percent were not on any government watch list or known to be Al Qaeda (search) members. Instead, they were "radicalized almost exclusively by the coalition invasion," the report said.

The Saudis provide money and propaganda for the insurgents, it said. Unlike fighters from poor Arab nations, Saudis sometimes bring in "personal funds between $10,000 and $15,000" to contribute, the report said.

There also is a system for spreading the news of suicide bombings carried out by Saudis, unlike suicide bombers from Algeria or Egypt, whose families may never be notified, the report said. Saudi bombers leave their colleagues a contact number to notify next of kin.

"The media attention their deaths as 'martyrs' bring to the cause ... is a powerful recruiting tool," the report said.

And Saudi exploits are exaggerated in Internet statements issued by insurgent groups. It noted that analysis of some lists of "martyrs" posted on Islamic militant Web sites found that some said to have carried out suicide attacks were living in Saudi Arabia.

Many of the Saudi fighters were inspired to go to Iraq by militant clerics, who also helped the young men get there, often through Syria.

In one case cited by the report, a 24-year-old Saudi angered by the U.S. invasion of Iraq was introduced by a cleric to a Yemeni Al Qaeda operative. The operative indoctrinated him and three of his friends, bought them plane tickets to Damascus in July 2003 and gave them a Syrian contact.

The Syrian took the men to the border and Iraqi handlers brought them to Tikrit, where they joined an insurgent "battalion" made up mostly of Saudis. The Saudi's friends agreed to become suicide bombers, but he declined and returned to Saudi Arabia, where he was arrested.