The 1937 "Rape of Nanking," a symbol of Japanese brutality during World War II, is under increasing attack from revisionist historians and veterans' groups here as a myth fabricated by the victorious allies.

In articles and books published here in recent months, they concede that some atrocities occurred. But they contend the death toll was nowhere near the 200,000 figure cited during war crimes trials after Japan's surrender in 1945.

"It was absolutely necessary for the trials to have a crime against humanity," said Masaaki Tanaka, author of a new book entitled "The Fiction of the Nanking Massacre." "In Japan there was no Auschwitz . . . Therefore they needed Nanking."

The debate threatens to reopen a bitter three-year-old dispute with China on this highly sensitive issue.

In 1982, Peking reacted angrily when the Japanese Ministry of Education proposed softening school textbook accounts of Japanese brutality in Nanking and other chapters in Japan's long war in China.

A relatively small group of people and organizations is publicly arguing the case. Still, their actions and the publicity they have received offer new evidence that the Japanese are gradually dropping taboos against questioning the victors' account of Japan's conduct in the war.

The Japanese Imperial Army seized Manchuria, in China's northeast, in 1932. By 1937, Japan had launched attacks all over China and had overrun large sections of the country. Some historians date the start of World War II to these attacks.

In December that year, Japanese troops advanced on Nanking, then capital of the Nationalist Chinese government of Chiang Kai-shek. With hundreds of thousands of the city's inhabitants huddled in a "safety zone" administered by neutral foreigners, Japanese artillery and bombers pounded the walled city.

Mainstream historians say that much of the bombing and shelling was indiscriminate, slaughtering many civilians in the city and on escape routes to the Yangtse River. Tanaka and other revisionists counter that most civilian deaths were unintentional, mistakes committed in "the heat of the battle."

But much of the debate concerns what happened after the city was captured on Dec. 12-13. According to testimony at the Tokyo war crimes tribunal, which in 1948 sentenced seven Japanese leaders to death and 18 to prison terms, the conquerors embarked on an orgy of murder, rape and pillage that lasted six weeks.

They executed tens of thousands of prisoners of war and men suspected of being soldiers out of uniform, according to testimony, and whole sections of the city were burned and their inhabitants killed. Soldiers were said to have raped thousands of women.

For China, the Rape of Nanking is unquestionable. Official Chinese accounts put the death toll at 300,000.

A spokesman at the Chinese Embassy here, noting that his government is watching the debate, said: "The Japanese invasion Army's killing of large numbers of civilians and soldiers who had thrown away their weapons is an historical fact."

Nanking years ago established a special historical archive on the incident. Currently, a mass grave there is being excavated and the city plans to erect a museum over it to commemorate the victims of the Japanese.

The revisionist theory on Nanking was first broached in the early 1970s. But in 1984, a torrent of articles and debate was unleashed. Advocates include Imperial Army veterans' groups and academics, with the influential Bungei Shunju magazine giving them much space.

One veterans' journal has published an article on it every month since last March.

Other historians, meanwhile, countered with a campaign to prove that Japan's acts were as horrible as alleged. This camp has been led by the powerful Asahi Shimbun newspaper group, a pillar of Japanese liberalism.

In December, nine Japanese scholars spent a week in Nanking interviewing survivors and examining historical documents and sites. The group, whose members tend to reject the revisionist position, plans to conclude a major study of the incident soon.

"For many years, the people of Nanking have been trying to ascertain what happened. They want to preserve the evidence," said Akira Fujiwara, a historian at Tokyo's Hitotsubashi University who headed the delegation.

The revisionists contend that the Japanese troops were generally well disciplined after the fall of Nanking. As evidence, they point to official letters and documents issued by a committee of 15 foreigners that administered the safety zone.

According to author Tanaka, in a total of 69 letters to Japanese authorities, the committee complained of only 49 civilian deaths caused by Japanese soldiers, and many of these were unconfirmed. A later survey of the city and environs by Chinese students, he said, turned up only about 2,150 civilian deaths caused by Japanese.

Foreign journalists who were present in Nanking, he said, used hearsay accounts in reporting mass executions after the occupation. In any case, he maintains, numbers quoted were nowhere near the 200,000 figure that gained legitimacy a decade later at the Tokyo trial and at a separate trial in Nanking.

The revisionist camp also points to reports that poorly disciplined Chinese soldiers on the run killed civilians during the battle's chaos, sometimes to obtain their clothes.

Attempts by attorneys for the Japanese defendants to introduce such evidence at the trials were unfairly quashed by the judges, according to Tanaka. "The purpose of the trials was to demoralize and create a sense of criminality" in Japan, he said.

In rebuttal, the Asahi Journal, a weekly magazine owned by the Asahi Shimbun newspaper group, recently published a 25-part series written by a reporter who spent months conducting research in China. Entitled "The Road to Nanking," it concludes that the tribunal's account of Japanese atrocities was essentially correct.

Similar views are voiced by Tomio Hora, author of a book on Nanking and professor of history at Tokyo's Waseda University. He cited records of two Chinese organizations that operated burial squads.

"The records of these two groups show 150,000 corpses were disposed of," Hora said. "In addition, the Japanese Army killed many prisoners of war and threw their bodies into the river and fired on people trying to escape along the river."

Hora concedes the burial records may be unreliable. But he estimates that a total of about 200,000 people died in the city. That includes all deaths, both soldiers and civilians, by combat and execution.

His own research suggests that "the Japanese Army had no respect for the safety zone at all," he said. Reports and complaints to the Japanese without a doubt understate the extent of the real crimes, he said. "People preferred to be silent, afraid of revenge."

The debate has also led to publication of diaries of Japanese soldiers who served at Nanking. One, put on display at a Kyoto peace exhibit last summer, tells of a Dec. 14 massacre of 500 Chinese men picked out from refugees in the belief they were soldiers who had abandoned their uniforms.

"The Chinese were too many for a platoon to kill with rifles , so we borrowed two heavy machine guns and six light machine guns from the Japanese Army company," the soldier wrote. The Chinese were mowed down in front of the city wall, he said.

Hora said that execution of prisoners was common in China. Members of one Japanese regiment have reported it killed 13,000 prisoners, he said. Revisionist historian Tanaka has acknowledged some deaths of this sort, but said that guerrillas could legally be shot under international rules of war.

In the 1982 textbook dispute, Japanese officials proposed deleting precise death tolls at Nanking and writing instead "many" deaths on the grounds that accurate figures were unknown.

The officials later agreed to restore the numbers but have deleted reference to rape on the grounds that soldiers have abused women in battle throughout history.