Wilfred Burchett, 72, an Australian journalist famous for the sympathy he showed the Marxist cause and the communist world while reporting from nations behind the iron curtain in both Europe and Asia, died yesterday in Sofia, Bulgaria.

Dispatches written by BTA, the official Bulgarian news agency that reported his death, did not include its cause.

In a career that spanned four decades, he covered China, Burma and the Pacific during World War II. He later accompanied Chinese troops into South Korea during the Korean conflict. He reported on the fighting in Southeast Asia while with Viet Cong forces and also was an aide to Cambodian Prince Norodom Sihanouk. Other Burchett datelines included Cuba, Angola, Moscow and Berlin.

He was the author of about 40 books that were translated and published in more than 30 countries. He reported for many prestigious newspapers including Le Monde of Paris, the Manchester Guardian and London Daily Express. His work also was carried by the Associated Press.

He was a vigorous man whose dedication to political causes destroyed much of his journalistic credibility. He was widely regarded as a communist sympathizer at the very least, but very possibly a communist intelligence officer, by many Western observers. "He told everyone, 'I can't join the Communist Party because I can't take the discipline,' but he didn't mind if people called him a communist," one friend said. "He called himself a progressive."

During the Korean conflict, he reported that American forces were engaging in "germ warfare," that British prisoners of war were kept in camps that "looked like a holiday resort in Switzerland." Needless to say, these observations were disputed by all with any degree of wit. Yet, because of his access to North Korean leader Kim Il-Sung, his work was widely watched for possible diplomatic signals.

He also reportedly interrogated Allied prisoners for their North Korean and Chinese captors. For these actions, his native Australia labeled him a traitor and revoked his passport in 1956. Mr. Burchett traveled for many years on North Vietnamese and Cuban passports until his Australian one was reinstated in 1972.

During the conflict in Southeast Asia, he spent time in Hanoi, where he reported for western and communist publications. He also was said to have been the person who decided which western journalists were allowed visas for North Vietnam, and was a close friend of Ho Chi Minh.

Over the years, Mr. Burchett made his home in Peking, Moscow, Vietnam and Paris. He had lived in Sofia for the past year. He was born in Melbourne, Australia. He covered communist trials in Budapest, reporting that the conviction of highly regarded Catholic archbishop was just, as were all communist actions during the Cold War that he covered from inside the Iron Curtain in the 1950s and 1960s.

A native of Melbourne, Mr. Burchett's father was a Methodist lay minister and farmer who was active in leftist organizations.

Though gifted in languages, poverty forced him to leave high school. He worked as a farm laborer, truck driver, vacuum-cleaner salesman and carpenter. He saved money, and in 1936 moved to London where he joined Thomas Cook & Sons, the travel agents.

He also became active in left-wing clubs and met the Soviet ambassador to Britain, Ivan Maisky. With Maisky's help, he opened the London office of Intourist, the Soviet travel agency. Mr. Burchett also became active in organizations getting Jewish refugees out of Nazi Germany.

During World War II he wrote from the jungles of Burma, American aircraft carriers and, of course, China. His big scoop came in 1945. Every other reporter then based in Tokyo was getting ready to cover the surrender ceremony. Mr. Burchett journeyed to Hiroshima to view the destruction there caused by the atomic bomb.

His dispatch, datelined Hiroshima, was phoned to a colleague in Tokyo and then splashed across the front pages of the world's newspapers. It was the first eyewitness account of the holocaust--and a good one. Many feel that his anti-Americanism was born here.

Mr. Burchett's survivors include his wife, Vessa, three sons and a daughter.