Iraqi Terrorists May Have Infiltrated Saudi Arabia, U.S. Experts Say : Military: Security is even tighter than usual. Ground movements are restricted.

U.S. military authorities said they believe Iraqi terrorists have infiltrated Saudi Arabia and are capable of striking when they choose.

Allied officers here also expressed heightened anxiety about a desperate military strike by Saddam Hussein--perhaps mobilization of his hidden air force for a bombing raid south into Saudi Arabia or the Persian Gulf.

In some areas of the region, security this weekend has become even tighter than the usual. Ground movements are restricted. Nerves already shot by periodic Scud missile attacks are strained yet again.

“The infiltrators have not committed any terrorist acts, but they probably are in a position to do so at a time of their own choosing--that’s the major concern,” said Marine Capt. John Borth, leading a patrol in a nearly deserted Saudi town near the war front. The battle-ready patrol swept through the area, unsuccessfully searching for infiltrators on the move south.

Borth said he believes infiltrators have already assisted Hussein by gathering intelligence on U.S. troop positions to assist Iraqi rocket targeting.

A senior American officer in Washington confirmed that Iraqi forces are “patrolling aggressively” across the border into Saudi Arabia at numerous points along the battlefront.

“It’s standard Soviet doctrine to infiltrate people” to do forward artillery spotting and to assess the strength of enemy units, the officer said.

Elsewhere in Saudi Arabia, reinforced gun emplacements and zigzag concrete roadblocks popped up overnight on the key road approaching a military base. Journalists were further warned against travel in the countryside, much of which has been posted as restricted.

At sea in the Persian Gulf, “I think we can expect something dramatic,” said Capt. Ernest F. Tedeschi of the U.S. guided-missile cruiser Valley Forge. The Aegis-class vessel, armed with missiles, is on station to protect America’s fleet of carriers operating in the cramped gulf.

Tedeschi, whose home is San Diego, spoke with unusual frankness and detail in a pool dispatch that passed through armed forces censors. The apparent goal is to increase military vigilance and perhaps further prepare Americans back home for a possible offensive by Hussein. Leading up to the weekend, Defense Secretary Dick Cheney and Pentagon officials also reminded the nation that Iraq retains offensive capabilities.

“It is sort of eerie,” said Navy Lt. West Brown, also aboard the Valley Forge. “What are they doing? I can’t sit here and believe he is giving in. I believe that he’s thinking of something. . . . He has a plan. I doubt it is a good plan.”

Ground terrorism and a 750-plane air force--a good part of which is believed to be usable--are two weapons that Iraq is known to possess and that it has been curiously slow to use, at least in the minds of the U.S.-led coalition commanders.

Saudi and U.S. pilots generally voice confidence that they can stop anything the poorly regarded Iraqi air force puts into the air. Aboard the Valley Forge, sailors share that optimism. But they said they worry about two things: an Iraqi daredevil who tries to blend in single-handedly with a wave of returning American warplanes or a massed air attack by everything Hussein has.

“We have enough Aegis cruisers out here to take care of pretty much his whole air force,” said Operations Spec. 2d Class Ray Fleming of California. But as he stood his watch, Fleming added an unsettling qualifier, “A few might get through.”

On land, Saudi private security agents warned war correspondents in writing. “So far the terrorist threat has not manifested itself. We should not be lulled into a false sense of security. The promise has been made by Saddam . . . Saddam Hussein is a man of his word.”

Additionally, residents of Eastern Saudi Arabia have been told for the first time to prepare for possible blackouts. Air raids, chiefly at night, have been commonplace in the war theater. But since Iraqi Scuds are ballistic missiles that free-fall without guidance, there has been no call for blacking out cities.

This latest warning of possible blackouts, on the other hand, is a further indication of allied worries about the potential for aircraft bombing raids.

U.S. officials this weekend reported destroying three loaded bombers on the ground in Iraq. These were heavy aircraft that an official said could reach “any target” in the war theater.

Saudi officials also have notified U.S. television operations in the region that they may have to shut down microwave satellite dishes. They would be juicy targets for Iraqi radiation-homing missiles. Usually these missiles seek to kill military radar systems, such as those that are the heart of the Patriot air defense system.

Meanwhile, Army bomb disposal experts studied the wreckage of an Iraqi missile launched into Saudi Arabia and blown out of the sky by a Patriot. Preliminary analysis by the 71st Ordnance Disposal Unit indicated it may not have been a Scud but a more sophisticated radar-homing missile.

This account includes dispatches from pool reporters reviewed by allied military censors.