Baghdad, Iraq ? Iraqi and U.S. forces captured a suicide bomber before he could detonate his explosive belt Thursday and announced a key suspect in the kidnap-slaying of Egypt’s top envoy to Iraq had been arrested in what was hailed as a blow to the terrorist network.

The thwarted suicide attack – just 150 feet from the Green Zone, the site of the U.S. Embassy and major Iraqi government offices – was intended to be part of coordinated assaults by a suicide car bomber and two pedestrians strapped with explosives.

The attackers apparently planned to detonate the car bomb first. Then the two pedestrians would blow themselves up in the midst of troops, police and rescue workers rushing to the scene, U.S. officials said.

The car bomb exploded successfully. But one pedestrian bomber was killed after an Iraqi policeman shot him, setting off his explosive vest, a U.S. statement said.

The surviving attacker was in critical condition at a U.S. military hospital in the Green Zone, the military said. Five policemen and four civilians were also injured by the blasts and gunfire, officials at Yarmouk Hospital said.

An Internet statement in the name of al-Qaida claimed responsibility for Thursday’s attacks, but the authenticity could not be confirmed.

An Iraqi bride and groom walk past rows of protective bomb blast walls surrounding a Baghdad hotel as they arrive Thursday with family members to spend the night after their wedding.

In another blow to the terrorist network, about 30 suspected al-Qaida members were arrested in the past week, including a key suspect in this month’s killing of Egyptian envoy Ihab al-Sherif and attacks on senior diplomats from Bahrain and Saudi Arabia, the U.S. command said.

Khamis Abdul-Fahdawi, known as Abu Seba, was captured Saturday following operations in the Ramadi area west of Baghdad, the military said. He is a suspect in the “attacks against diplomats of Bahrain, Pakistan and the recent murder of Egyptian envoy” al-Sherif, the U.S. statement said.

Another top suspect, Abdullah Ibrahim al-Shadad, or Abu Abdul-Aziz, was arrested during a raid Sunday in Baghdad, the statement said. It identified him as the operations officer for al-Qaida in Iraq, led by Jordanian Abu Musab al-Zarqawi. Abu Abdul-Aziz was cooperating with coalition forces, according to the U.S. command.

In an Internet statement Thursday, al-Qaida in Iraq acknowledged that Abu Abdul Aziz had been apprehended but played down his importance.

Al-Qaida also denied any role in the suicide car bombing Wednesday that killed 27 people – including 18 children and teenagers and an American soldier – in Baghdad. The bomber detonated his SUV as U.S. troops were distributing candy and toys in the mostly Shiite Muslim New Baghdad area.

“We, the al-Qaida organization in Iraq, announce that we are not in the least responsible for the New Baghdad operation that took place Wednesday,” said the statement posted and signed by Abu Maysara al-Iraqi, the al-Qaida spokesman.