BAGHDAD Ñ Sunni insurgents backing Abu Mussib Al Zarqawi have expressed alarm at the prospect of a defeat by the U.S.-led coalition in Iraq.

An audio tape said to be from Al Zarqawi charged Muslim clerics with letting down the insurgency "because of your silence."

On Wednesday, Al Zarqawi, with a $25 million bounty on his head, was the target of a major manhunt in the Sunni Triangle, Middle East Newsline reported. Iraqi military sources said Al Zarqawi was said to have been seen in an area south of Fallujah.

Islamic sources said that for the first time in more than a year the Tawhid and Jihad group led by Al Zarqawi appears to have lost control over many of its insurgents in the Sunni Triangle.

The sources said Iraqi and U.S. assaults on major insurgency strongholds in such cities as Baghdad, Fallujah, Mosul, Ramadi and Samara have resulted in heavy insurgency casualties and a break in the command and control structure.

Over the last few days, Al Zarqawi supporters have appealed for help from Al Qaida and related groups. The sources said Al Qaida's allies, including the Salafist Brigade for Combat and Call, have sought to increase recruitment of Muslim volunteers to fight the coalition.

The Internet has also reflected the growing concern that Islamic insurgents would be routed in Iraq. A message posted on an Islamic website appealed for help from Islamic insurgents in Afghanistan, Chechnya, Pakistan and the Palestinian Authority.

The message, posted by a purported insurgency supporter who used the name Abu Ahmed Al Baghdadi, acknowledged that the Sunni insurgency has been harmed by the U.S.-led offensive in Fallujah. Al Baghdadi said insurgents have lost their haven in Fallujah, but asserted that Al Zarqawi has acquired a broader base for operations and recruitment.

For his part, Al Zarqawi has also expressed concern over the U.S. military operation against Fallujah, Mosul and other insurgency strongholds.

On Wednesday, an audio tape posted on an Islamic website and purportedly from Al Zarqawi accused Muslim clerics of failing to support the insurgency in Iraq.

"You have let us down in the darkest circumstances and handed us over to the enemy," the message said. "You have stopped supporting the holy warriors. Hundreds of thousands of the nation's sons are being slaughtered at the hands of the infidels because of your silence."

In early November, Al Baghdadi posted a plan for the Tawhid group to take over Iraq. Islamic sources said Al Baghdadi was believed to be pseudonym used by a major Islamic operative.

Al Zarqawi accused unnamed clerics and scholars of preventing Muslims from joining the Sunni insurgency in Iraq. He said Muslim clerics abandoned the insurgents to the United States.

"Are your hearts not shaken by the scenes of your brothers being surrounded and hurt by your enemy?" Al Zarqawi asked.

"How long will you continue to abandon the nation to the tyrants of the east and of the west, who are inflicting the worst suffering, cutting the throats of the holy warriors, the best children of the nation, and taking its riches?"