Iraq's most senior Sunni politician issued a desperate appeal Sunday for Arab nations to help stop what he called an "unprecedented genocide campaign" by Shiite militias armed, trained and controlled by Iran.

Elsewhere, the U.S. military reported five American soldiers were killed, apparently lured into an Al Qaeda trap.

Adnan al-Dulaimi said "Persians" and "Safawis," Sunni terms for Iranian Shiites, were on the brink of total control in Baghdad and soon would threaten Sunni Arab regimes which predominate in the Mideast.

"It is a war that has started in Baghdad and they will not stop there but will expand it to all Arab lands," al-Dulaimi wrote in an impassioned e-mail to The Associated Press.

Sunni Arab regimes throughout the Middle East fear the growing influence of Iran's Shiite theocracy with radical groups like Hezbollah and Hamas as well as the Syrian regime. Raising the specter of Iranian power reaching the Arab doorstep, unlikely in the near-term, betrayed al-Dulaimi's desperation.

But his fears of a Shiite takeover of Baghdad were not as farfetched. Mahdi Army militiamen have cleansed entire neighborhoods of Sunni residents and seized Sunni mosques. Day by day, hundreds have been killed and thousands have fled their homes, seeking safety in the shrinking number of majority Sunni districts.

The fighters, nominally loyal to radical Shiite cleric Muqtada al-Sadr, are believed to operate as death squads blamed for much of the country's sectarian slaughter.

Sunni extremists, many with Al Qaeda links, are responsible too, mainly through massive bombings, often carried out by suicide attackers.

Like al-Dulaimi, the United States accuses Iran of providing the Shiite militia with sophisticated armor-piercing roadside bombs, other weapons and training. Iran denies the allegations.

Al-Dulaimi resorted to the extremely harsh language a day after Prime Minister Nouri al-Maliki, a Shiite, returned from his second visit to Tehran since taking power 14 months ago.

The outburst reflected growing anger in the Sunni establishment over perceptions of al-Maliki as a deeply biased sectarian leader with links to Iran.

"Arabs, your brothers in the land of the two rivers and in Baghdad in particular are exposed to an unprecedented genocide campaign by the militias and death squads that are directed, armed and supported by Iran," al-Dulaimi said.

And he castigated fellow Sunnis in the Middle East, saying they "did not make any move and did not even bother to denounce what is taking place against your brothers at the hands of Iranian militias and death squads."

The 75-year-old al-Dulaimi heads the Iraqi Accordance Front, the largest Sunni political bloc in parliament. The coalition of parties pulled its six Cabinet ministers from al-Maliki's Shiite-dominated government Aug. 1.

Five days later, government ministers loyal to former Prime Minister Ayad Allawi, a secular Shiite, launched a boycott of Cabinet meetings. That left the government without any Sunni Arab members, except the politically unaffiliated defense minister.

Major political figures were expected to hold a rare summit with al-Maliki this week in Baghdad to address the government crisis.

The five American soldiers were killed Saturday in Arab Jabour, a district just south of Baghdad where Shiite militiamen and Al Qaeda linked fighters have battled for control and are now under attack by soldiers of the 3rd Infantry Division.

Maj. Gen. Rick Lynch, the task force commander, said a sniper killed one soldier, then lured his comrades to a booby-trapped house where four died in an explosion when one of them stepped on a hidden bomb. Four others were wounded in the blast, Lynch told the AP.

At least 37 people were killed or found dead in sectarian violence nationwide. Nearly half of that number, 17, were tortured bodies discovered in Baghdad, officials said.

At a news conference Sunday, al-Maliki defended his Iranian sojourn and said he would continue traveling to neighboring countries and asking for help to curb violence. He was expected to be in Syria next week, but the trip has not been announced.

"Iraq has turned into the center of terrorism. Iraq will only succeed through reconciliation," he said.

Al-Dulaimi's remarks focused not on reconciliation but on Arab nationalism and perceived Iranian threats.

"I call on all Arabs — Muslims, presidents and kings and people — to intervene and urge the Iraqi government to end this crisis. I call on them to stand beside Iraqis against violence and the oppression that come to us from Iran and its agents."