One of Moqtada al-Sadr’s most senior aides in Baghdad was arrested by US and Iraqi troops in a pre-dawn raid targeting death squads yesterday, prompting the cleric’s followers to threaten “disastrous” consequences.

Sheikh Abdul Hadi al-Darraji was captured in Baladiyat. Followers claimed that armoured vehicles broke down the walls around the mosque where he was captured and that soldiers led him away handcuffed and blindfolded.

The move came as Robert Gates, the new US Secretary of Defence, arrived in Basra to visit British and other coalition commanders, and two days after Prime Minister Nouri al-Maliki told The Times that he was prepared to act even against militias from parties in his own Shia-led coalition.

An Iraqi government spokesman confirmed that Sheikh al-Darraji was detained, but insisted that it was a security matter and that the Government was not “targeting a particular group or party”. The US military confirmed that Multi-National Corps “advisers” accompanied Iraqi special forces on a raid in the eastern suburb, near Hojatoleslam al-Sadr’s stronghold in Sadr City.

A statement did not name the principal target among three people detained, but said that he was a “high-level, illegal armed group leader” suspected of links to “Baghdad death squad commanders”.

It claimed to have “credible intelligence” that the suspect played a leading role in the “organised kidnapping, torture and murder of Iraqi civilians” and the “assassination of numerous Iraqi Security Forces members and government officials”.

Ali al-Dabbagh, a government spokesman, said the raid had the Prime Minister’s backing. “If he proves innocent then he will definitely be released and if not, he will be dealt with according to law,” he said.

However, Abu Hawra, Sheikh al-Darraji’s deputy, accused US forces of trying to “create problems” in the Iraqi Government with the arrest.

He insisted that the sheikh was not a commander in the Mahdi Army and insisted on his immediate release.

“People here [in Sadr City] are very angry and I can see preparations within the locals and Mahdi Army that may lead to a disastrous reaction,” said Abu Hawra. Although the Sadrists claim that the raid was actually spearheaded by US not Iraqi forces, Falah Shalshel, head of the Sadr block in Parliament, said that Hojatoleslam al-Sadr had urged his followers to “remain calm and be patient”.

US commanders have recently emphasised the importance of assuring disaffected Sunnis that the new operation to control Baghdad must be non-sectarian. However, coalition forces have backed down before after squaring up to Hojatoleslam al-Sadr, amid unease among Shia political leaders at confronting him directly.

In August 2004, after surrounding the Mahdi Army in Najaf, US Marines allowed Grand Ayatollah Ali al-Sistani to broker a deal enabling Hojatoleslam al-Sadr’s forces to escape.

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