Iraqi analysts say foreign fighters, including some with ties to Al Qaeda, could be cooperating with former Saddam Hussein regime members and other terrorists here in attacks on coalition and coalition-ally targets. Experts tell Fox News it is a very volatile mix.

"The relationship between them makes them very powerful, " Dana Ahmed Majid, security chief for the northeastern Iraq Kurdish province of Sulaymaniyah (search), told me.

Sulaymaniyah province contains the mountains where Ansar al-Islam (search), the Kurdish Islamic militant group suspected of having links to Al Qaeda, had been based before this spring's war with Iraq.

During the fighting, Ansar al-Islam's bases were attacked by both coalition and secular Kurdish forces. Members of the group were killed, captured or fled over the Iranian border nearby. Intelligence experts say many have been returning and causing problems.

Fox News had exclusive access to several captured Ansar al-Islam members. All were Iraqis, but all were also suspected of involvement in terrorist acts and collaborating with foreign Islamists.

One prisoner, who refused to be identified, admitted to being an Ansar al-Islam member. He'd been accused of entering Iraq from Iran with explosives in his car. He told me the group had needed time to reorganize and regroup but was now "powerful" again. His attitude certainly reflected continued defiance.

"I just want to tell Americans one thing," he told me. "Get out of Iraq if you want to live."

Many attacks against coalition forces and their Iraqi allies have occurred in central Iraq. There have been suspicions foreigners have joined forces with ex-Ba'athists and others there.

According to another alleged terror group member, Ansar al-Islam leaders who had received training in Afghanistan gave instructions to 200 to 300 mostly Arab fighters to leave northeastern Iraq, "head south" and stay there.

"They will continue to do that," this prisoner told me, "as long as Americans are inside the country."

Terrorist acts have spread to northern Iraq. Last month, an office of the Patriotic Union of Kurdistan (search) in the city of Kirkuk was hit by a car bomb. We have been told that two CIA agents were meeting Kurdish officials at the time. Six Iraqis died in the blast. Ansar al-Islam is suspected of involvement.

Many Iraqis say that only foreigners, or Iraqis instructed by foreigners, could be capable of the homicide bomb attacks witnessed lately. Such methods were not widely employed in Iraq when Saddam Hussein was in power.

Still another terror suspect showed us how he attached sticks of dynamite to his chest and back in a foiled attempt at blowing up another secular Kurdish office in the north. He claimed the Ansar leaders told him that if he carried out the attack, they would give his destitute family money and a new home.

"That sounded like a good idea," he remarked.

Coalition officials says their intelligence-gathering abilities have been improving markedly. They have also been tightening Iraq's borders, and whatever foreigners they are finding are being rounded up.

Most officials in Iraq also say the number of foreigners involved in anti-coalition attacks is low — maybe only 5 percent of the terrorist rank and file. But considering the punch they pack, according to Kurdish security boss Majid, "five percent is too much for these kinds of terrorist activities."

Greg Palkot currently serves as a London-based senior foreign affairs correspondent for Fox News Channel (FNC). He joined the network in 1998 as a correspondent. Follow him on Twitter@GregPalkot.