Baghdad, Iraq ? U.S. and Iraqi forces swooped into a mosque complex in east Baghdad on Friday and detained a top aide to radical anti-American cleric Muqtada al-Sadr, the latest in a series of operations aimed at eviscerating the leadership of the Mahdi Army militia.

The raid drew immediate criticism from the Iraqi government, which complained it had not been consulted. An aide to Prime Minister Nouri al-Maliki, who owes his job as Iraqi leader to al-Sadr’s backing, said the operation was not part of a coming joint U.S.-Iraq security drive.

Under the plan, to which President Bush has committed an additional 21,500 American troops, U.S. commanders have been promised a freer hand against both Sunni insurgents and Shiite militiamen.

“There was no coordination with the Iraqi political leadership and this arrest was not part of the new security plan,” Sadiq al-Rikabi, the al-Maliki adviser, told Al-Arabiya television. “Coordination with the Iraqi political leadership is needed before conducting such operations that draw popular reactions.”

Abdul-Hadi al-Darraji was captured in the early morning raid and his bodyguard was killed in what Abdul-Zahra al-Suweiadi, a senior al-Sadr aide, called a “cowardly act.” Al-Sadr’s office said al-Darraji was media director for the cleric’s political movement and demanded his immediate release.

“America is playing with fire and our patience is beginning to fade,” said Abdul-Razzaq al-Nidawi, an al-Sadr aide in the Shiite holy city of Najaf. “This savage barbarian act will not pass peacefully.”

The U.S. military, in a statement that did not name al-Darraji or mention the Mahdi Army by name, said special Iraqi army forces operating with U.S. advisers had “captured a high-level, illegal armed group leader” in Baghdad’s Baladiyat neighborhood, which is adjacent to Sadr City, the Mahdi Army stronghold.

“Iraqi forces detained him based on credible intelligence that he is the leader of an illegal armed group (involved in) … the organized kidnapping, torture and murder of Iraqi civilians. The suspect is also reportedly involved in the assassination of numerous Iraqi Security Forces members and government officials,” the U.S. statement said.

An Iraqi child holds a framed photo of Muqtada al-Sadr, Imam Ali and Mohammed Sadiq al-Sadr during Friday prayers in the Shiite enclave of Sadr City in Baghdad, Iraq. U.S. and Iraqi forces arrested one of Muqtada al-Sadr's top aides Friday in Baghdad, his office said, as pressure increases on the radical Shiite cleric's militia ahead of a planned security sweep aimed at stemming the sectarian violence ransacking the capital.

It said two other suspects were detained for questioning.

In an interview with an Italian newspaper, al-Sadr said the U.S.-Iraqi security crackdown already has begun.

And he confirmed reports that 400 Mahdi Army men have been arrested.

The La Repubblica interviewer quoted al-Sadr as saying he feared for his life and stayed on the move constantly. His aides have told The Associated Press he seldom sleeps in the same place for two nights in succession.

Al-Sadr said his militias would not fight back immediately because Islam forbids killing during the Muslim holy month of Muharram, which starts Friday for Sunnis and today for Shiites.

“Let them kill us. For a true believer there is no better moment than this to die: Heaven is ensured,” he was quoted as saying. “After Muharram, we’ll see.”

Al-Sadr said he is being targeted.

“For this reason, I have moved my family to a secure location. I even have had a will drawn up, and I move continuously in a way that only few can know where I am,” he was quoted as saying by La Repubblica.

Some of al-Sadr’s militia commanders have said al-Maliki has stopped protecting the Shiite fighters under pressure from Washington. They have claimed at least five top commanders were captured or killed in recent months.