David Truong had a favorite way of introducing himself: "My family was the first in Vietnam to own a Mercedes."

His family also was one of the wealthiest in Saigon and eventual one of the most celebrated during the final years of the war. His father Truong Dinh Dzu ran as a peace candidate against then-president Nguyen Van Thieu in 1967 and recieved a five year prison sentence for his campaign advocating negotiations with the Vietcong.

That was two years after David Truong had arrived in the U.S. to study at Stanford University to become an educated member of the ruling class and thrive a Mercedes, he would later say. Instead, with his father's imprisonment, Truong became a well-known antiwar activist in the U.S., respected enough to write numerous magazine and newspaper articles, an articulate spokesman for the cuase of a negotiated peace and a penniless student.

Yesterday, in an Alexandria federal courthouse, Truong was indicted on charges of allegedly stealing American documents and sending them to Hanoi, the capital of communist Vietnam. Truong sate through the hearing impassively, the center of controversy once again.

To the Vietnamese community, Truong represented the Left, the Vietnamese Left that often was scorned by the refugees who chose to emigrate to the United States as the war came to an end in spring of 1975. Many Vietnamese immigrants applauded Truong's arrest for its political implications, others decried it for the same reason.

"We say 'at last the Americans understand where the danger is'," remarked Le Thi Anh, copublisher of Vietnam News, which calls itself "the voice of non-Communist Vietnamese."

To a Harvard doctoral candidate in history and former head of the Vietnamese Resource Center, the arrest offered a different interpretation. "I know the U.S. government is on a witch-hunting thing against the Vietnamese community," said Ngo Vinh Long. "But I don't know why they piced on David."

His arrest has brought to the surface not only these political questions, but also the divisions and hatreds among the Vietnamese community in the Washington area.

When he first arrived here, an overweight Vietnamese student with a quick mind and cultured manner, David Truong was named Trung Dinh Hung and he was the favorite son of a favored family. He has grown up in a walled villa in suburban Saigon, as accustomed to French cuishne as his native Vietnamese.

His father had won fame for his legal work and had avoided the war by avoiding politics. In 1967, when the father was arrested for his campaign for peace, a court deemed the offense "an action that has weakened the anti-Communist will of the people and the army."

Friends said David Truong began reappraising the war while his father served his sentence of five years at hard labor in Chihoa prison. David also moved to the East Coast, eventually to Cambridge, Mass., after he graduated from Stanford. He had no money - his father's imprisonment had seen to that - and he spent his time reading Vietnamese, French and English-language material about the war.

"He was in terrible financial straits then," Long recalled. Truong became Long's roommate in Cambrige, babysitting for Long's children and doing research for him in exchange for food and houseing.

"He took care of the kids when we went to classes," Long said. "Even when he went away to Washington he would come back to visit them, Hoi (the 8-year-old son) and Thaian (the 4-year-old girl)."

With Long, Truong worked at the Vietnamese Resource Center in Cambridge and when he came to Washington he continued to be on its payrool. By 1974, he had become an outspoken critic of the war, especially the American involvement, and he was quickly making enemies anti-Communnist Vietnamese, both here and in Vietnam.

"He was aprested? Ah, very good. . . . There are many ARVN (South Vietnam's defeated army) soliders who would like to fight him," said Ha Thuc Ky, chairman of the anti-Communist League of Human Rights Committee here Washington.Friends say Truong's twin goals of finding a negotiated peace for the Vietnam war and finding a way back to "civilian" life often were frustrated by the same conflicts plaguing most Vietnamese family.

Even today, his only brother is at a political re-education camp in Vietnam. His father and mother, on the other hand, lead normal lives in Vietnam. They raise vegetables and chickens, sellings eggs in the market, and they used to receive letter from their son David in America.

David was academic, he was very active in the antiwar movement, and he was also very astute about Vietnamese politics," said William Good-fellow, a friend of Truong's since 1974 and a fellow at the Center for International Policy here.

Once the war was over, and the Socialist Republic of Vietnam established, Truong and Nguyen Thi Tuc Thoa established the Vietnamese American Reconciliation Center here. The two produced a newsletter to distribute at the camps set up around the U.S. to house the new immigrants. They said they wanted to present both sides of the Vienamese war to these refugees and make them less frightened about the regime that won the war.

"I admire him in many ways," says Nguyen Ngo Bich, who first met Truong in this country nearly 14 years ago. "He was extremely bright, extremely dedicated - and also extremely poor. There are always people who believe in a certain cause that you may not agreed with, but you admire them just the same."

Bich was director general of information here for the Thieu regime, and now is Vietnamese community director for Arlington public schools system.

Friends said that Truong had asked the Vietnamese government for pemission to return to his native country, either for a visit or premanently. APparently he was turned down. "I understand they (the Vietnamese) were very cold to his request to return," said one friend, who declined to be identified.

So Truong and Thoa disbanded their reconciliation center to go back to school. Troug was a graduate student in finance at George Washington University when he was arrested yesterday.

He also was a part-time employe of the Animal Health Institute, a trade association that paid him $9,000 a year to manage its warehouse.

His arrest came as a "shock and surprise," a spokesman there said. 'He had to mix around (at his job) and he got along well with everybody," the spokesman said.