JEDDAH, 26 April 2004 — Over the last year there has been a dramatic rise in terrorist activity in the Kingdom, matched by a decisive government response. A chronology of the main events:

May 12, 2003: Bombers attack a Riyadh compound housing mostly Westerners, resulting in 35 deaths including 10 Americans and seven Saudis.

May 27, 28, 2003: Eleven suspects are arrested in Madinah. Weapons, bomb-making materials and fake IDs are seized. Saudi national Abdul Monim Ali Mahfouz Al-Ghamdi is arrested following a car chase.

May 31, 2003: Yousif Salih Fahd Al-Ayeeri, a key Al-Qaeda operative and fund-raiser, is killed while fleeing from a security patrol. Two officers are killed and three others wounded in the clash. A second gunman is arrested.

June 7, 2003: Saudi Arabia identifies 12 suicide bombers responsible for attacks on three Riyadh compounds and says 10 suspects are still at large. Interior Minister Prince Naif says 25 people have been arrested.

June 14, 2003: A terrorist cell in the Al-Attas building in the Khalidiya neighborhood of Makkah is raided. Two police officers and five suspects are killed in a shootout. Twelve suspects are arrested.

June 20, 2003: Security forces in Makkah arrest four Saudi women after raiding a flat rented by a suspected terrorist.

June 27, 2003: One of the men wanted in connection with the May 12 bombings, Ali Abdul Rahman Saeed Al-Faqaasi Al-Ghamdi, surrenders.

July 3, 2003: Key suspect in the Riyadh bombings, Turki Nasser Al-Dandani, and three other wanted terrorists are killed in a shootout with security forces.

July 21, 2003: Authorities foil imminent terrorist attacks against vital installations and arrest 16 members of terrorist cells after searching their hideouts in farms and houses in Riyadh, Qasim and the Eastern Province.

July 25, 2003: Three men are arrested at a checkpoint in Makkah for possessing printed material that included a “religious edict” supporting attacks on Western targets.

July 28, 2003: Security forces kill six suspected terrorists and injure one in a gunfight at a farm in Qasim.

Aug. 13, 2003: Security personnel arrest five terrorists after four policemen and a militant were killed in a shootout in Riyadh two days earlier.

Sept. 23, 2003: Security forces surround a group of suspected terrorists in an apartment in Jizan. One officer is killed and four others are injured in an ensuing gun battle. Two suspects are arrested and another killed.

Oct. 5, 2003: Police arrest three suspects during a raid in the desert east of Riyadh.

Oct. 8, 2003: Security forces raid a farm in the northern Muleda area of Qasim and arrest a suspect. Three other suspects flee. Two security officers suffer injuries. Large quantities of bomb-making material and light weaponry are found on the farm.

Oct. 20, 2003: Security forces raid terror cells in various parts of the country, including Riyadh, Al-Majmaa, Makkah, Jeddah and Qasim. Plastic explosives, homemade bombs, gas masks and large quantities of assault rifles and ammunition are seized.

Nov. 3, 2003: Police arrest six Al-Qaeda terrorists after a shootout in Makkah. Two terrorists are killed and one security officer wounded. A large cache of weapons, including rocket-propelled grenades, is seized.

Nov. 6, 2003: Two terrorists blow themselves up during a raid in Makkah, hours after another is shot dead in Riyadh.

Nov. 7, 2003: Security forces trap two terrorists in Riyadh. The duo commit suicide by blowing themselves up.

Nov. 8, 2003: Suicide bomb attack on a residential compound kills many people, a day after the United States warns of terrorist strikes in the Kingdom.

Nov. 25, 2003: Security forces arrest at least 10 terrorists in various parts of the Kingdom including one described as “very dangerous.” Some are linked to Al-Qaeda.

Dec. 6, 2003: The Interior Ministry releases a list of 26 most wanted terrorists. Rewards ranging from SR1 million to SR5 million are offered.

Dec. 7, 2003: Security forces arrest 25 suspects in connection with the May 12 bombings in Riyadh.

Dec. 8, 2003: One of the most wanted terrorists is killed and another arrested following a shootout with security forces in Al-Suwaidy district in Riyadh.

Dec. 30, 2003: Mansour ibn Muhammad Faqeeh, one of the 26 most wanted terror suspects, surrenders to security forces.

Feb. 13, 2004: The Interior Ministry warns residents in the capital against a possible terrorist attack. It says that a car laden with explosives registered to a wanted suspect could be used in the attack.

Feb. 14, 2004: The Interior Ministry offers SR7 million reward for information leading to the discovery of a GMC Suburban loaded with explosives.

March 15, 2004: Two of the most wanted terror suspects are killed in a shootout with police. One is identified as Khaled Ali Al-Haj, a Yemeni national.

April 5, 2004: Security forces shoot dead a suspected terrorist and wound another during a car chase in an eastern Riyadh neighborhood.

April 12, 2004: A member of the security forces is killed and a terrorist gunned down during a clash in eastern Riyadh.

April 13, 2004: Four policemen are killed by machine-gun fire in two attacks on the road linking Riyadh and Qasim. The first of two explosive-laden cars is discovered. Gunmen open fire at officers at a checkpoint on the road to Qasim. Police defuse two car bombs and seize a third car loaded with arms.

April 18, 2004: Eight terror suspects linked to violent clashes with security forces in the capital are arrested. Three large vehicle bombs — each with over a ton of explosives on board — are defused.

April 19, 2004: Security forces defuse two truck bombs apparently kept ready for use in terror attacks in Riyadh.

April 21, 2004: Terrorists launch a car bomb attack against government buildings in Riyadh, killing five people and injuring 140 others.

April 22, 2004: Four of the most wanted terrorists are killed in a shootout in Jeddah.