BAGHDAD, Iraq — Seven American service members were reported killed yesterday in insurgent attacks, as the U.S. military announced the capture of a top militant believed responsible for at least some of the recent wave of suicide bombings.

The deaths brought to eight the number of American servicemen killed in action over the weekend, an unusually high number after several weeks of reduced U.S. casualties that have prompted some military officials to speculate that the insurgency is waning.

A dramatic spike in insurgent violence that has killed nearly 300 people over the past 10 days has mostly targeted Iraqis and Iraqi security forces.

For the first time since April 28, no suicide bombings were reported yesterday, after an unprecedented 10-day onslaught of attacks that has terrorized much of the country.

The U.S. military deaths included three Marines and a sailor who were killed in an engagement Saturday in Haditha, in the western province of Anbar, when their convoy was ambushed by insurgents operating from inside the local hospital, a military statement issued yesterday said.

First a car bomb destroyed one of the convoy's vehicles, which crashed and set the hospital on fire. Then, insurgents in the hospital attacked the Marines with rockets and small-arms fire, the statement said.

Two soldiers assigned to the 2nd Marine Division died yesterday near Khalidiyah, which lies between the troubled towns of Fallujah and Ramadi, also in Anbar province. Their vehicle was hit by an improvised explosive device during combat operations, the military said.

Another soldier died yesterday and one was wounded when their patrol was struck by an improvised explosive device in Samarra, north of Baghdad.

In Baghdad, the U.S. military said it captured a top insurgent believed responsible for many of the suicide bombings in Baghdad, including nine attacks April 29, and the assault by a large group of insurgents on the Abu Ghraib prison April 2.

Amar Adnan Muhammad Hamzah al-Zubaydi, also known as Abu al Abbas, was captured during an early-morning raid in Baghdad on Thursday, according to a military statement.

Al-Zubaydi was a top aide to the Jordanian-born militant Abu Musab al-Zarqawi, and he prepared numerous car bombs for dispatch to Baghdad at his farm in Yusufiyah, in the notorious Triangle of Death south of Baghdad, the statement said.

It wasn't clear whether the pause in suicide bombings yesterday was linked to the capture Thursday. There have been at least three suicide bombings since then, including the twin attacks Saturday on a private security convoy that killed 27 Iraqis and two American security contractors.

According to the statement, al-Zubaydi was a "key figure" who helped prepare vehicles, selected targets, assigned suicide bombers and facilitated the entry of foreign fighters into Iraq, the military said.

Also seized with Zubaydi were letters, notes and sketches for a plan to assassinate a senior government official.

"The capture of Abu Al Abbas prevents one of the most wanted terrorists in Iraq from further terrorizing Iraqis and delaying them from a peaceful and stable environment," the statement said.

Abu al Abbas and another recently captured al-Zarqawi associate, Ghassan Amin, have both contributed information on the "operations, logistics and locations of Abu Musab al-Zarqawi network members, foreign fighters and suicide bombers" in Baghdad and western Iraq, it added.

Also yesterday, the military reported the detention of 33 terrorist suspects in Baghdad on Saturday, including a high-ranking military officer in the former regime, and 17 terrorist suspects in Babil.

Meanwhile, the Shiite-dominated Iraqi parliament approved four more Sunni Arabs yesterday to serve as government ministers.

One of the four Sunnis rejected the post on the grounds of tokenism, tarnishing the Shiite premier's bid to include the disaffected minority believed to be driving Iraq's deadly insurgency.

Parliament approved all six of the nominees placed before it yesterday by Prime Minister Ibrahim al-Jaafari.

Information from The Associated Press

is included in this report.