The Patriot missile, a sudden hero of the allied arsenal in the war against Iraq, may be working even better than the Pentagon is letting on.

The ground-to-air missile-killing system was said to score nine hits late Sunday and early Monday on Iraqi Scud-type missiles fired into Saudi Arabia. It made a successful combat debut Friday by destroying a solo Scud that was approaching a huge airbase in Dhahran.Those are the only Patriot firings the Pentagon has acknowledged. But a British officer says he was told of two more successful intercepts, and accounts from local residents mesh with the officer's statements.

According to the officer, the two unreported Scud intercepts were made by Patriots at a Persian Gulf port used as a major military staging area. The port is not far from a large Saudi oil refinery at Ras Tanura.

An Army spokesman said he had no information about those reported Patriot firings. The spokesman's efforts to check with the commander of the Patriot units that would have been involved were unsuccessful because the Sunday night volleys from Iraq kept the Patriot crews so busy.

A Saudi official from the area refused an interview request on the topic, saying, "I'm aware of an incident like that, but I'm not going to talk to you about it."

The Saudi government has been going to great lengths to portray life in the oil-rich Eastern Province as normal despite the war. It hopes to prevent civilian panic and to discour-age American and other expatriate workers vital to its oil industries from fleeing.

It would be impossible to hide Patriot firings at Dhahran because dozens of journalists are staying at a hotel just off the air base. But the port area where the British officer reported the Patriot firings is isolated from the media because of combat coverage restrictions.

There was also a peculiar occurrence involving Patriots in the Saudi capital of Riyadh.

The official Saudi Press Agency issued an unusual statement saying a source in the joint American-Saudi command had told it two Riyadh-based Patriots had been accidentally fired because of a technical error. It was unclear why a Saudi agency would issue a statement about an American weapons system.

After the Scud attack on Riyadh, reporters found a crater that appeared to contain missile remnants, but they were unsure whether it might have been caused by a Scud or an errant Patriot.

The Patriot, made by Raytheon Co., is a radar-guided system mounted in a rectangular-shaped box that swivels on its mount. When fired, the missiles vault from their pods with a sonic boom and race across the sky toward incoming targets.

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GRAPHIC\ Patriot targets Scud missiles

The Patriot mobile missile system is designed to defend U.S. ground forces against air attacks. Iraqi Scud missiles streaked into Saudi Arabia Sunday night, but they were destroyed by Patriot rockets.

Radar identifies and tracks incoming Scud missile.

Patriot missile launcher Can carry four guided missiles.

U.S. Patriot: Length: 209 inches, Diameter: 16 inches, Range: Over 50 miles.

How the system works:

1. Patriot launched and locks onto target.

2. Radar guides Patriot to incoming Scud.