Security forces have killed 15 Islamic militants in four days, including three on the most wanted list, in the most intensive fighting yet seen in Saudi Arabia's two-year war on terror — a sign the kingdom may have Al Qaeda (search) on the defensive.

The latest slain militant was Abdul-Rahman Mohammed Mohammed Yazji (search), killed Wednesday by police in a raid in a rundown industrial area of the capital, Riyadh. Yazji is suspected of involvement in a November 2003 bombing of a housing complex for foreign workers that killed 17 Arabs.

Yazji was holed up in a two-story building hidden away in a maze of alleys full of garages and car parts shops. Police swooped down on the site in the morning, said neighbors, who heard explosions and saw flames leaping from the building.

Yazji was No. 25 on the country's list of 26 most wanted terrorists, and his death means the government has killed or arrested 23 of the listed militants.

The raid came a day after the end of the kingdom's longest and deadliest shootout with militants — a three-day battle in the desert town of Rass, northwest of Riyadh. Special forces killed Nos. 4 and 7 on the list, Kareem Altohami al-Mojati (search), a Moroccan, and Saud Homood Obaid al-Otaibi (search), a Saudi and a leading Al Qaeda figure in the kingdom. Twelve other militants were killed in the raid and six were captured.

Interior Minister Prince Nayef warned militants: "Either come back to your senses or you'll face death."

"We'll carry on (the fight) until it's over and that won't be long, God willing," Nayef said, in remarks carried by the official Saudi news agency.

Brig. Gen. Mansour al-Turki, an Interior Ministry spokesman, said Saudi security forces had gained the upper hand against the militants.

"We have a security system in place that is working," he told The Associated Press.

Saudi Arabia launched its crackdown on militants in 2003 after a string of suicide bombings, kidnappings and gun attacks claimed by a branch of Usama bin Laden's Al Qaeda terror network. The attacks were an alert for Saudis that bin Laden was targeting the rulers of the nation of his birth, not just the West.

"There's no doubt that terrorists in Saudi Arabia are struggling for survival," Khalil al-Khalil, a Saudi terror expert, said of the militant groups. "Their ability to organize and plan has been severely incapacitated. They are very weak, both organizationally and morally."

But he warned that attacks were likely to continue because Al Qaeda is still finding new recruits, particularly through radical clerics.

"Its hard to say at what rate they are recruiting. Definitely they have sympathizers, but the sympathy for them is drying up," al-Khalil said.

The top fugitive from the three figures from the wanted list still at large is Saleh al-Aoofi, believed to have become the new leader of Al Qaeda in the Gulf region after his predecessor, Abdel-Aziz al-Mogrin, was killed in June.

A statement on the official Saudi Press Agency reported Yazji's death in Wednesday's raid and said another militant was captured, but officials did not release his name.

The two militants killed in Rass, 220 miles northwest of Riyadh, were among a group that security forces raided on Sunday, sparking a battle that lasted until Tuesday night. Fourteen militants were killed and 14 security personnel wounded.

A Web site where statements purportedly from Al Qaeda have been posted in the past on Wednesday announced the deaths of al-Mojati and al-Otaibi and invited contributors to congratulate them on their "martyrdom."