Nearly 900 Iranian students shouting "Death to the shah" marched and chanted through downtown Washington yesterday, provoking hundreds of angry Americans into a counterdemonstration of curses, jeers and flag waving rage.

Scores of police on foot, horseback and motor scooters formed a moving human wall between the Iranians and the office workers, construction workers and American students who screamed obscenities and, on several occasions, pelted them with eggs.

"Go home! Go home!" yelled those along the parade route. "Take your oil and shove it!"

When the Iranian marchers started chanting "Death, death, death to the shah," bystanders countered "Death, death, death to Khomeini!" -- referring to Iranian leader Ayatollah Ruhollah Khomeini, who sanctioned the recent student takeover of the U.S. Embassy in Tehran.

"I haven't seen people get so mad since World War II," said Ned Childress, a Navy veteran and systems analyst at the Veterans Administration. Childress said whole offices in the VA building at 15th and I streets NW emptied before lunch as workers ran out to jeer Iranians.

"I am sick to death of these monsters. I don't think they should be allowed to demonstrate," said Virginia Hobson, 53, a secretary. Hobson followed the marchers down 14th street, her face contorted with rage, yelling, "Go home! Go home!"

Official Washington from the White House and the State Department to the mayor's office, watched the confrontation tensely, fearful that violence here might further endanger the 65 Americans held hostage in Tehran since the embassy takeover last Sunday.

Minor scuffles broke out between Iranians and counterdemonstrators along the parade route at the beginning and end of the six-hour march, but no injuries were reported.

D.C. police arrested three of the counterdemonstrators, one for disorderly conduct and two for throwing eggs.

The anti-Iranian anger here -- and the sense of frustration and futility that seemed to encompass it -- was mirrored in other, smaller demonstrations around the country.

From the moment the march began, it became a magnet for the anti-Iranian feelings of Washington workers infuriated by the embassy seizure and demands by Iranian demonstrators for return of Shah Mohammad Reza Pahlavi, now undergoing cancer treatment in a hospital in New York.

Waving American flags and hastily lettered signs with such messages as "Deport the Iranian Extortionists," businessman in three-piece suits and well-dressed older woman joined construction workers in hard hats shouting obscenities at the demonstrators.

Most of the Iranian demonstrators were students who came from campuses around the country for the Washington march. They stared stolidly ahead and ignored the bystanders who hurled insults across three police lines. Occasionally, some demonstrators would stare hard at the young men who made obscene gestures or yelled, "F___ you, you ragheads!"

"These people are concerned about what's going on over there" (in Tehran) said one Iranian, Mohammed Nik, a graduate student at American University. "This is a natural reaction.

"The only thing that's disconcerting is that I didn't expect them to show their anger this way, I didn't expect them to be this rude."

In Beverly Hills, Calif., police used night sticks to break up several fights between Iranians -- demonstrating in defiance of police orders -- and counterdemonstrators who had come out to harass them. Police said about 50 persons, mostly Iranians, were arrested.

Police in Springfield, Mass., escorted 30 protesting Iranians to waiting buses after more than 1,000 angry people surrounded them. The crowd pelted the buses with rocks, bottles and eggs.

Officials of the International Longshoremen's Association announced that ILA members will refuse to load cargo into ships headed for Iran. In addition, the AFL-CIO Transport Workers Union and Air Transport Division announced that no Iranian aircraft would be serviced by their members until the American hostages in Tehran were freed.

Similar confrontations took place at the University of Nevada-Reno and in Charleston, S.C., where a small group of Iranians at the Baptist College burned an American flag.

Even where there were no Iranian demonstrators, the American anger over events in Tehran could be felt. A bedsheet emblazoned "Death to the Ayatollah" hung over a Boston expressway, and in Provo, Utah, a huge banner reading, "Deport Iran" appeared on a mountainside overlooking Brigham Young University.

The Washington march began shortly after 11 a.m. as groups of Iranian students gathered in McPherson Square, where more than 400 D.C. and U.S. Park police officers were waiting to escort the march. Small knots of anti-Iranian demonstrators jostled some of the marchers as they arrived.

The Iranians then followed a zigzag three-mile route through downtown Washington, circling in front of the National Press Building before moving north up 15th Street below office workers jeering from windows and waving American flags.

Some counterdemonstrators sat down ahead of the Iranians twice in an effort to block the parade's progress. Police dislodged them without making any arrests.

As the marchers moved west on H Street toward George Washington University, the counterdemonstrators ahead of them waved American flags and broke into snatches of patriotic song, half-shouting "The Star-Spangled Banner," "God Bless America" and "Battle Hymn of the Republic."

Behind the three-block long cavalcade Mayor Marion Barry and D.C. Police Chief Burtell Jefferson rode in a brown sedan. Barry said he wanted to get "a personal assessment" of the situation.

"This is serious business," he said. The mayor had decided Thursday night to permit the protest after listing to the concerns of State Department and White House officials who feared violence.

Throughout most of the day yesterday Barry defended his granting of the parade permit as a tactical move, which he said effectively contained the demonstrators who he believed would march in any case.

But he found himself jeered by numerous bystanders by his decision and aides said his office received numerous calls of protest.

Last night he decided to cancel the city permits that would have allowed the demonstrators to continue on Saturday and Sunday.

Yesterday's march wound through the GW campus before the Iranians turned south on 23rd Street NW and headed for the State Department.

Once along C and 22nd streets in front of the State Department's main door, the marchers kicked off their shoes, and knelt on the streets to pray together.

They stayed seated for another two to three hours as several of the 700 or more D.C. and park police surrounding them gathered in small groups, chatting and lighting cigarettes. Near the main door, a few students from George Washington and other local schools continued to scream occasional epithets at the Iranians.

State Department workers, who had decked out the nearby light posts with U.S. and Irish flags for the visit of Irish Prime Minister Jack Lynch, stood in front of the building or at its windows watching.

Most refused to comment, but one 30-year-old official said, "I'm ready to deport them, quite frankly. Khomeini is an outlaw for defying the very fundamentals of international law."

The Iranian demonstrators, however, said that the siege of the U.S. embassy in Tehran is the responsibility of the U.S. government, which had permitted the shah to come to New York for medical treatment.

"I'm not concerned with whether he has cancer. He is a criminal and should be tried," said Mohammad Badr, a business administration student at St. Louis University. "We are peaceful," he added. "We don't hate the American people, just the American government.

Police officials, concerned about the possibility of violence as the demonstration broke up, offered to drive the Iranians in 12 buses from the congested area in front of the State Department.

Most of the demonstrators, however, refused to take the offer "from the government of the oppressor," as one put it, and instead sat on the pavement until their fellow demonstrators brought cars and vans to take them away.

Two counterdemonstrators, Alan David Graves, 22, of Detroit, and Herbert Williams, 26, of Alexandria, were charged with throwing eggs at the Iranians. A third, Michael Paul Daiuto, 31, of Wheaton, was charged with disordely conduct.

Washingtonians appeared to be venting their anger not just against Iranians but against the U.S. government, which they say has weakened the strong arm of America.

Jack Waldron, 32, an appliance salesman, ran sweating and panting alongside the parade of students shouting obscenities at them. Every once in while he would clench his fists, arch his shoulders and let off a deep sigh.

"I just had to do that, it makes me feel better," said Waldron, who took off from work and scrapped a noonhour doctors appointment to yell at the protesters.

"You speak for me," one TV cameraman whispered to Waldron after he had just screamed "f------ whores."

"This situation calls for a strong response from America," said Waldron. "It's not just the idea that 61 Americans are being held hostage in the American Embassy. It's the idea that America's reputation in world diplomacy is at stake."

A crowd of onlookers -- government workers, construction workers, businessmen, students, downtown shoppers -- cheered Waldron on.

"I'm sick and tired of these people thinking they can push American around. It just makes me sick," said Mary Wyatt, an electronics technician, who walked alongside the Iranians near George Washington University shouting, "Death to Iran! Death to Khomeini!"

In front of the Islamic Center at 2551 Massachusetts Ave., N.W., about 200 local university students chanted and waved flags and signs that urged motorists to "Honk if you're mad at what's happening in Iran."

This triggered incessant honking from passing motorists, like Joe Lawrence, a Bowie salesman, who blasted his horn, lowered his car window and yelled, "If Khomeini is a spiritual leader, then Adolf Hilter was a saint."

Many of the students, who broke into chants of "Two, Four, Six, Eight -- Serve Khomeini on a plate," from time to time, said this was their first time at a protest march.

In other parts of the demonstration route, American protesters were more bitter and appeared to be trying to provoke the Iranians to break police lines.

"C'mon out here, faggot!" shouted one man who would identify himself only as an Internal Revenue agent, as he beckoned to one Iranian protester.

Like many other U.S. citizens, a veterans official, who would not give his name, said he was angered by the fact that the D.C. police seemed to be protecting the Iranian demonstrators.

"Look at the way they're facing," he said, scanning the row of policemen, carrying night sticks, who separated the Iranians from the onlookers. "They're ready to beat on me. What kind of a system is this?"

Not all the American onlookers, however were there to heckle the Iranians.

"I've never seen people so ugly," said Richard J. Feeney, public affairs director for the Independent Meat Packers Association. "There was a stockbroker and a construction worker near me and they were just yelling at them."