Target of Terror

The truck bomb that killed 19 American soldiers and wounded hundreds was the deadliest terror strike ever against a U.S. target in the Middle East, since 1983, when a bomb killed 241 U.S. service personnel in Beirut.

The source of the explosion was believed to have been a bomb strapped onto a fuel truck. The blast left a crater 35 feet deep and 85 feet wide, three times the size of the crater left by the Oklahoma City bombing. Windows shattered nearly a mile away.

SECURITY

* Security had been tightened in recent months after reports of cars driving slowly by or stopping briefly. However, military officials acknowledged that Saudi police did allow some auto traffic to pass along the roadway by the barracks.

* The truck was parked outside the base’s security perimeter but was still only about 35 yards from the nearest building. Security experts say that a safer--but admittedly impractical--perimeter would have been at least 1,300 yards.

* Suspicious of the fuel truck, authorities tried to evacuate two nearby apartment buildings, but the bomb went off a couple of minutes later, at 10:30 p.m. (12:30 p.m. PDT).

THE U.S. PRESENCE

* Of the 40,000 Americans in Saudi Arabia, about 5,000 are military. The base at Dhahran plays a key role in monitoring military flights and activities in Iraq and Iran.

* Main Air Force units are from Eglin AFB in Florida; Hill AFB, Utah; Shaw AFB, S.C.; Cannon AFB N.M.; and Little Rock AFB, Ark. The units form the 4404th Composite Air Wing, flying 60 aircraft in the region, including F-15s, F-16s, and AWACS surveillance aircraft.

* The Air Force has set up a toll-free number to answer questions from family members about Air Force personnel affected by the bombing: (800) 253-9276.

Source: Times staff and wire reports