TARMIYAH, Iraq - A roadside bomb blast killed three U.S. soldiers and wounded eight others north of Iraq's capital today, the military said.

Lt. Col. Clifford Kent, a spokesman for the U.S. Army's 3rd Infantry Division, confirmed "there were soldiers killed and wounded" in an explosion, but he had no other information.

"We're trying to figure out what the details are," Kent told The Associated Press.

Witnesses said the attack took place around midday in Tarmiyah, 20 miles northeast of Baghdad.

Residents saw about a dozen injured U.S. soldiers lying on blood-splattered ground after the attack.

"I was heading to our house ... there was a group of American soldiers walking in the road while around five Humvees were parking behind them," said Waleed Nahed, 35, who lives in the area. "I heard a very loud explosion and I saw bodies flying."

Nahed and Alaa Nagy, 22, who works as a guard at a nearby factory, said helicopters landed in the area 15 minutes after the explosion and took the injured soldiers away.

The road was immediately blocked off by the U.S. military and Iraqi security forces.

In Baghdad, the government said today that Iraqi forces captured a key aide to Jordanian-born terrorist Abu Musab al-Zarqawi, who leads an insurgency affiliated with Osama bin Laden's al-Qaida network.

The man, identified as Talib Mikhlif Arsan Walman al-Dulaymi, also known as Abu Qutaybah, was captured Sunday during a raid in Anah, about 160 miles northwest of Baghdad, a government announcement said.

"Abu Qutaybah was responsible for determining who, when and how terrorist network leaders would meet with al-Zarqawi," the government said.

In Tikrit, a suicide bomber wearing a police uniform blew up his car at police headquarters, killing at least 15 people in Saddam Hussein's hometown in the bloodiest of several attacks Thursday.

The suicide bombings and other attacks came as politicians negotiated behind the scenes to forge the alliances needed to win enough backing in the 275-seat National Assembly for the post of prime minister.

The U.S. command said two American soldiers were killed Thursday and two wounded in separate bomb attacks, one northeast of Baghdad in Qaryat, and a second near Samarra, west of Qaryat. The military said a third soldier was killed in action west of Baghdad, in Anbar province.

A suicide bomber killed five other people in Iskandariyah, 30 miles south of the capital, when he blew himself up in front of the local headquarters of a key Shiite alliance member, the Shiite Supreme Council for the Islamic Revolution in Iraq.