TERROR IN OKLAHOMA CITY : Bomb Threats Force Thousands of Federal Workers to Evacuate : Security: All of the threats turn out to be hoaxes. Extra guards are posted, and searches are carried out at U.S. buildings around country.

In the aftermath of the Oklahoma City blast Wednesday, bomb threats forced the evacuation of thousands of employees in more than a dozen other federal buildings from Wilmington, Del., to Kansas City, Mo., to Portland, Ore., officials said.

All the threats proved to be hoaxes. Still, workers returned to their desks or left work early Wednesday, shaken both by the tragedy in Oklahoma and the personal link that they felt to it. The sense of security of most federal employees in their workplaces has been seriously shaken, government administrators said.

As precautions against bombings at thousands of federal facilities, extra guards were posted, buildings and garages were searched and employees were told to watch for anything suspicious or unusual.

Atty. Gen. Janet Reno said that “nothing has materialized” from the rash of threats that she attributed to “terribly misguided individuals.” Both she and President Clinton said that measures would be taken to secure other federal buildings and employees.

In Washington, security was tightened at the White House and on Capitol Hill. Federal officials are already in the midst of re-evaluating security procedures at the White House after a small plane crashed onto its lawn and a man opened fire on the building last year.

Bomb threats are not unknown at federal office buildings. During anti-war demonstrations while the United States was involved in the Vietnam War, such threats were numerous and many were received during the Persian Gulf War. But, veteran security personnel said after Wednesday’s bombing in Oklahoma, the threats now seem much more ominous.

“It makes it more real,” said Mike Sisk, building manager at a federal office facility in Omaha, where one threat was received Wednesday.

“Over the years, the number of actual bombings has been very, very few,” said Stan Burczyk, chief of security for the 800 federal buildings in the six-state region headquartered in Chicago. “I’m sure that this certainly gives people the idea that, if it happened there, it could happen here.

“It’s very disheartening to see this happen,” added Burczyk, a 23-year veteran in his job. He said that four threats were received in his region but only in only one case, at a Cincinnati federal building, did employees evacuate.

In Boston, some Internal Revenue Service employees noticed a door open that should have been locked. Considering the blast in Oklahoma, police decided to evacuate the 2,000 employees in the 24-story building, despite a steady rain. Many employees opted to go home instead of returning to their offices.

“There were also a number of hoaxes elsewhere in Boston,” said Bob Dunfey, regional administrator of the federal General Services Administration in Boston. “It created a lot of anxiety.”

In Denver, even though no threats were received, worried parents and administrators decided to close a child-care center in the federal customs house.

In Omaha and Kansas City, offices were emptied after bomb threats were received at midday. Explosive-sniffing dogs searched the buildings but nothing was discovered.

Not long after lunch time, a caller said that a “pipe bomb was set to go off at 2 p.m.” at the Edward Zorinsky Federal Building in downtown Omaha.

“In view of what happened in Oklahoma City, we took it very seriously,” said Sisk, who added that it was the first such threat that the nine-story building had received in the six years he has worked there. He decided to send all 1,200 employees home.

The tension and urgency among the employees, he said, were completely different from the usual fire drill.

Other federal buildings that received phoned-in bomb threats forced temporary evacuations in New York City; Boise, Ida.; Rochester, N.Y.; Ft. Worth; Spokane, Wash.; Portland, Ore., and Miami, according to officials. Related bomb scares also forced the evacuations of the City Halls in Boston and Ft. Worth., according to Hap Conners, spokesman for the GSA in Washington.

(BEGIN TEXT OF INFOBOX / INFOGRAPHIC)

Evacuation Across Nation

Threats Nationwide

The following sites were among the buildings evacuated after the explosion in Oklahoma City, because of telephoned bomb threats or signs that a bomb may have been planted:

1. Federal building in Portland, Ore.

2. Santa Ana office building housing FBI

3. Anaheim City Hall

4. Riverside City Hall

5. Federal building in Omaha

6. Boston City Hall

7. Boston John F. Kennedy Federal Building

8. New York City’s police headquarters

9. Capitol in Wilmington, Del.

10. Justice Department in Washington

11. Capitol in Washington

Source: Associated Press