JIZAN, Saudi Arabia -- Shootout by shootout, surrender by surrender, Saudi authorities are working their way through a list of al-Qaida suspects in a bombing assault that brought Muslim terrorism to the heart of the kingdom.

The latest suspect to die in a nationwide dragnet -- one that has featured unprecedented cooperation with the United States as well as unusual openness -- was Zubayr al-Rimi. Al-Rimi, also known as Sultan Jubran Sultan al-Qahtani, was killed Tuesday when Saudi security forces raided an apartment where they said a new terror attack was being plotted.

A U.S. diplomat in Saudi Arabia said Thursday the raid in Jizan, 600 miles south of Riyadh, was proof of the high level of cooperation between the United States and Saudi Arabia, though he could not confirm the Saudis were working on an FBI tip. The diplomat, speaking on condition of anonymity, did say agents from the FBI and Treasury Department are in the kingdom working on an anti-terror task force with Saudi investigators.

In Washington on Wednesday, John Pistole, assistant director of the FBI's counterterrorism division, said the raid in which al-Rimi died came after the FBI received information on his whereabouts. Pistole was speaking to a subcommittee of the U.S. House Financial Services Committee.

Al-Rimi was among 19 suspects in May 12 suicide bombings at housing compounds in Riyadh that killed 35 people, including nine Saudi attackers. Saudi officials have said the 19 were in contact with al-Qaida, the group suspected in the Sept. 11, 2001, attacks in the United States.

Prince Bandar bin Sultan, Saudi Arabia's ambassador to Washington, said in Arizona on Wednesday that al-Rimi was "the No. 2 al-Qaida" man in Saudi Arabia.

Of the 19 suspects, al-Rimi and seven others have been killed in recent months. Three have surrendered or been captured, and Saudi officials say four were among the May 12 suicide bombers, leaving four at large. Several other suspected extremists not on the list have been killed, and about 200 have been arrested.

The May 12 bombings were dramatic evidence al-Qaida is at work in the kingdom, birthplace of the terror group's founder, Osama bin Laden. Bin Laden accuses the West of trying to destroy Islam and criticizes Arab regimes like Saudi Arabia's that are close to Washington.

The housing compounds targeted May 12 were mainly inhabited by Americans, Britons and other foreigners, but Saudis living there also died. The shock over the attack, which killed Arabs and other Muslims, seemed to change the way some Saudis think about al-Qaida.

Saudi officials, who had previously played down the idea of al-Qaida operating in the kingdom, launched a series of highly publicized raids that have found large caches of weapons and snared dozens of suspected militants. And King Fahd and other members of the royal family and government have mounted a war of words against extremist thought, telling Saudis that Islam condemns terrorism and helping terrorists.

The kingdom had been under U.S. pressure since the Sept. 11, 2001, attacks to do more to combat terrorism. It took five months for Saudi officials to even acknowledge that 15 of the hijackers were Saudi, and they were accused by some Americans of moving slowly and fitfully in cooperating with U.S. anti-terror investigators.

The U.S. diplomat said Saudi cooperation had increased since May 12.

He said the government's unusual public stance in the anti-terrorist campaign reflected its new commitment. In the past, he said, officials might have tried to deal with such matters behind closed doors so as not to embarrass the families of those involved. In Saudi culture, the acts of an individual reflect on the honor of the family and tribe.

The names and pictures of the 19 suspects were shown on state-run Saudi television days before the May 12 attacks. They had escaped a raid in which security forces seized a large cache of weapons and explosives. Saudi officials have never said what tipped them off to the 19, but they seem to have suspected something like the Riyadh attack was being planned.

Al-Rimi is believed to have been the chief deputy of Abu Bakr al-Azdi, also known as Ali Abd al-Rahman al-Faqasi al-Ghamdi, the former top al-Qaida man in Saudi Arabia who surrendered to Saudi authorities June 26.

In Arizona on Wednesday, Nail A. Al-Jubeir, an official with the Saudi Embassy in the United States, said al-Azdi was "singing like a bird."