Profile of Terror Group Ansar al-Sunna

Dec. 21, 2004 — -- A group that identifies itself as the Ansar al-Sunna Army has claimed responsibility for today's attack in the northern Iraq city of Mosul, which killed at least two dozen people, many of them U.S. soldiers. The group also claims responsibility for attacks that have taken more than 1,000 lives over the last 15 months.

Ansar al-Sunna is known to use videos of rocket attacks and roadside bombings as part of its recruiting and training campaign.

"They're such an underground and clandestine group that I don't think anyone really knows about them," said counterinsurgency expert Maj. James Gavaris.

What is known, however, is that the group officially declared its existence in September 2003, uniting several militant groups inside Iraq. They distribute their videos in mosques where they are most likely to find supporters. Some members come from other countries, but most are Iraqis.

"To the extent we understand what its structure is, it does have some foreign elements, but it is largely Iraqi," said military analyst Tony Cordesman, an ABC News consultant.

U.S. officials are concerned that after American forces drove insurgents out of the former insurgent stronghold of Fallujah, some went to the Mosul area in northern Iraq, including members of Ansar al-Sunna.

They are believed to have cooperated with other Sunni extremists who want to convert Iraq into an Islamic state. U.S. intelligence officials say the total number of insurgents in Iraq has remained fairly steady -- from 12,000 to 16,000 -- but that does not include thousands of sympathizers who provide help to them, and thousands more who refuse to aid authorities in their capture.

"We see some leaders captured but we see new leaders emerging," Cordesman said. "And one real problem is that a lot of the insurgents are now far more experienced, far better trained. They know how to work better in cells."

Part of Ansar al-Sunna's recruiting campaign is to boast about their efforts, largely the reason why they were quick to take credit for today's deadly attack.

ABC News' John Cochran filed this report for "World News Tonight."