From Emperor of Japan: Meiji and His World, 1852–1912, by Donald Keene (Columbia U. Press, 2005), Kindle pp. 492-493:
Everything seemed to be going favorably for the Japanese when reports sent by foreign newspaper men who had witnessed the occupation of Port Arthur not only horrified readers abroad but for a time threatened Japan’s reputation as a modern, civilized country. The first report on the Japanese troops’ actions after conquering Port Arthur was made by Thomas Cowen, a foreign correspondent of the Times of London. After leaving Port Arthur, he reached Hiroshima on November 29 and had an interview the following day with Foreign Minister Mutsu. Cowen astonished Mutsu with his detailed descriptions of the ghastly scenes he had witnessed. That night Mutsu sent a telegram to Hayashi Tadasu:
Today I met with a Times correspondent who has returned from Port Arthur. He says that after the victory the Japanese soldiers behaved in a outrageous manner. It seems to be true that they murdered prisoners who had already been tied up, and they killed civilians, even women. He said that this situation was witnessed not only by newspaper men of Europe and America, but also by officers of the fleets of different countries, notably a British rear admiral.
The immediate reaction of the Japanese government to this and similar dispatches that appeared in the foreign press was to send out reports favorable to the Japanese. Bribes were given to Reuters to circulate pro-Japanese articles. Some newspapers like the Washington Post were directly paid to print articles favorable to Japan. Various foreign journalists were by this time in the Japanese pay.
Military censorship of the Japanese press was initiated at this time. A set of four regulations was drawn up, headed by the following instructions: “Reports should record insofar as possible true facts concerning acts of loyalty, courage, righteousness, and nobility and should encourage feelings of hostility toward the enemy.” Those who violated these regulations would be suitably punished.
Worldwide attention was drawn to the events that had occurred at Port Arthur by a brief cable dispatch from James Creelman, a foreign correspondent of the New York newspaper the World:
The Japanese troops entered Port Arthur on Nov. 21 and massacred practically the entire population in cold blood.
The defenseless and unarmed inhabitants were butchered in their houses and their bodies were unspeakably mutilated. There was an unrestrained reign of murder which continued for three days. The whole town was plundered with appalling atrocities.
It was the first stain upon Japanese civilization. The Japanese in this instance relapsed into barbarism.
All pretenses that circumstances justified the atrocities are false.
The civilized world will be horrified by the details. The foreign correspondents, horrified by the spectacle, left the army in a body.