Signing Ceremony Poses a Major Challenge for Keeping Peace in D.C. : Security: Possibly the largest contingent in recent history will protect thousands of dignitaries.

The thousands of dignitaries from overseas and across the nation invited to witness today’s historic signing of the Mideast peace agreement present an extraordinary protective challenge for government security specialists.

Perhaps not since President John F. Kennedy’s funeral 30 years ago, when Charles de Gaulle, then France’s president, marched arm-in-arm down Pennsylvania Avenue with other world leaders have so many government officials and other celebrities descended on the nation’s capital on such short notice.

The signing poses “a dangerous and volatile situation” because opponents of the pact include factions in the Arab and the Israeli communities with great potential for violence, Wayne Gilbert, former assistant FBI director in charge of intelligence, said in an interview.

As a result, a security contingent that is possibly the largest in recent Washington history will be pressed into service. The ceremony has sent executives of the FBI, Secret Service and State Department into action, with help from such other agencies as the U.S. Park Police and the District of Columbia Police Department.

Their task goes beyond providing protection at the signing ceremony at 11 a.m. (8 a.m. PDT) on the White House lawn, which will be attended by President Clinton, Israeli Prime Minister Yitzhak Rabin and PLO Chairman Yasser Arafat as well as two former U.S. Presidents, most of the Congress, Cabinet secretaries, Supreme Court justices, numerous lesser Israeli and Palestine Liberation Organization officials, prominent Jewish and Arab Americans and a sprinkling of other luminaries.

Security arrangements will also be needed for the entire time foreign officials are on U.S. soil. Their presence “invites a special problem because they have to show up at predictable places,” meaning airports and hotels, a U.S. intelligence official said.

Parts of Pennsylvania Avenue on the north side of the White House and E Street on the south side are expected to be closed from 10 a.m. EDT until 1 p.m., a police spokesman said Sunday.

In addition, the Ellipse, a grassy park on the south side of the White House, will be closed to pedestrians from 5 a.m. EDT until the ceremony is over.

The observation deck at the top of the Washington Monument will be closed part of the day because it offers an unimpeded line of fire to the White House South Lawn, where the ceremony will take place, a Park Service official said.

But the FBI’s Gilbert and other security specialists say the relatively short time between disclosure of the agreement, the announcement of the ceremony and the event itself could work to the government’s advantage.

“From a security standpoint, the short notice is a dream,” Gilbert said. “Potential terrorists haven’t had much time to plan, to get organized, and terrorist plots take some time to hatch.”

Given that condensed time span and the extensive precautions, “If anything is going to happen, it’s likely to be in a source country like Israel or Jordan rather than someone trying to penetrate the massive security that will be in place here,” Gilbert said.

A government source said the FBI “is reaching out to its sources of intelligence, keeping in touch with everyone” to detect any trace of planned terrorist activity.

The source said the super-secret National Security Agency, which has the ability to monitor electronic communications around the world, “also will be listening in real time and immediately reporting any suspicious conversations.”

The government has also reactivated the multi-agency counterterrorism network established during the Persian Gulf War, an Administration official said Sunday.

The network taps into intelligence agencies on six continents and brings together wide-ranging partners, including hard-line Arab regimes that have previously offered financial, logistic, military and political support to several Palestinian and Islamic extremist groups that are now considered potential spoilers of Mideast peace efforts.

The counterterrorism campaign during the 1990-91 Gulf crisis was the most effective international effort ever organized. Despite widespread fears of attacks on U.S. and allied targets, Iraq and its hard-line supporters in the Arab world were able to carry out only a handful of small and largely inconsequential acts of terrorism.

Officials of the Treasury Department, parent agency of the Secret Service, declined to discuss their specific security arrangements, on grounds they never want to tip off potential terrorists about what is or is not being done.

The Treasury Department, however, was expected to put into place many of the measures common to Presidential inaugural parades and visits of key heads of state, such as placing law enforcement officers armed with rifles on rooftops in the vicinity of the White House and sealing manhole covers along the neighboring streets.

Sgt. Joseph Gentile, a police spokesman, said D.C. officers will mainly assist with traffic control. “These are members of our special operations division who also are well-trained in handling demonstrations and related security arrangements, but we will be taking orders from the federal government,” Gentile said.

At the White House itself, officials were considering issuing special lapel pins for senior staff members to admit them to the South Lawn signing ceremony. Lesser Presidential aides will have to watch from their offices.

Times staff writers Robin Wright and David Lauter contributed to this story.