WASHINGTON - Iraqi and U.S. forces have detained a top aide to radical Shi’ite cleric Moqtada al-Sadr in an operation in eastern Baghdad Friday.Al-Sadr’s office said the man arrested is its media director, Sheik Abdul Hadi al-Darraji.

A U.S. military statement did not identify the detainee, but described him as a leader of an illegal armed group involved in the kidnapping, torture and murder of Iraqi civilians. It also said the man detained today was linked to wanted Shi’ite death squad leader Abu Dura.

Iraqi Prime Minister Nouri al-Maliki has vowed to crackdown on Sunni insurgents and Shi’ite militiamen in an effort to stem the escalating sectarian and insurgent violence in the country.

Separately, the U.S. military said one American soldier died and three others were wounded in a roadside bomb blast in northwest Baghdad Thursday.

In other news, the military announced Friday that Iraqi forces captured the suspected leader of several al-Qaida in Iraq terrorist cells during raids in the Samarra region this week. It said all of the raids were Iraqi operations with U.S. forces providing support.

And, Iraqi forces shot and killed one insurgent after his suicide vest failed to detonate near a check point in a suburb of Ramadi, the capital of the volatile Anbar province.