Saudi authorities have indicted 991 suspected militants on charges that they participated in terrorist attacks carried out in the kingdom over the last five years, the interior minister said Tuesday.

The legal proceedings mark a significant step in Saudi Arabia's fight against terror. Authorities had been reluctant to hold trials for terrorism charges that could result in death sentences until they had shown the public that every effort had been made to give the men a chance to repent.

"In the past few years, the kingdom has been the target of an organized terrorist campaign linked to networks of strife and sedition overseas," said Interior Minister Prince Nayef in his statement carried by The Saudi Press Agency.

"This campaign targeted the way of life, economy and principles of Saudi society and sought to create chaos," he added. "It has direct links to a deviant group that adopts the (mind-set) of al-Qaida."

The militants have been responsible for more than 30 attacks in the kingdom since May 2003, Nayef said. Those attacks killed 164 people, including 74 security officials, and wounded 657 security officials and 439 civilians.

Another 160 attacks were foiled.

Nayef's statement did not specify whether all the suspects were in custody or their nationalities.

The government fears a public backlash against its crackdown if it takes overly harsh measures against the militants, and it wants to avoid accusations that it is just trying to please the United States.

There is some sympathy for Saudis who leave the country to perform jihad in occupied Muslim countries. Many of those who have returned from imprisonment in Guantanamo Bay or Iraq have been placed in rehabilitation programs to encourage them to renounce terrorism.

Nayef said the militants' actions have affected the reputation of Islam and charity work, "attaching the label of terrorism to Islam and Muslims."

Nayef said that three tons of explosives have been seized from the militants. Thousands of missiles, automatic weapons, pistols, rifles, as well as cyanide, have also been seized, he said.

Saudi Arabia, the birthplace of Al Qaeda leader Usama bin Laden, has pursued an aggressive campaign against militants since May 2003, when they first began their strikes in the kingdom. Subsequent attacks targeted oil installations, government buildings and other compounds.

There have been no major attacks since February 2006, when suicide bombers tried but failed to attack an oil facility at the Abqaiq oil complex, the world's largest oil processing facility, in eastern Saudi Arabia.

It was not clear from the statement whether the trials would start immediately or be delayed until December after al-Adha feast, as has been written in some newspapers.