GENERAL SANTOS, Philippines — The discovery of two men believed to have been soldiers in the Imperial Japanese Army deep within the mountains of Mindanao Island in the southern Philippines leads one to wonder: What have they been doing for the 60 years since the end of World War II?

Prior to the outbreak of the Pacific War, there were about 26,000 Japanese living in the island's main city, Davao, which was known as the Japanese Kingdom.

Today, the area is rife with Islamist extremists, and the Philippine government has lost control of some parts of it. Yet somehow, the men believed to be Yoshio Yamakawa, 87, and Tsuzuki Nakauchi, 85, have survived this era of change.

According to Hikaru Miyake, the 62-year-old chairman of an association of Japanese in Davao, many Japanese moved to the region before the war to grow jute, a fiber used largely in burlap and twine.

When the war began, many of these permanent residents were drafted as civilian employees of the army, later fleeing with Imperial Japanese Army troops when U.S. forces made landfall on the island.

But the majority of these residents-cum-soldiers who lost their lives during the war did not fall to U.S. bullets but to infectious and endemic diseases such as malaria and to indigenous tribesmen in the mountains.

According to local sources, while many expatriates returned to Japan out of fear of retaliation at the hands of Filipinos, some chose to stay and moved to rural areas where they concealed their nationality.

Thus Yamakawa and Nakauchi could easily have passed undetected in the mountains. But today, Mindanao is home to a number of extremist Islam groups, including the Moro Islamic Liberation Front (MILF), which is seeking to establish an Islamic state on the island.

While the vicinity around General Santos is a base for commerce for the southern part of the island, it is also the gateway to a terrorist highway through which foreign extremist groups that have close ties with local extremist Islamic groups pass on their way to other areas in which they are active.

It is unclear if the two Japanese men had any kind of relationship with the terrorist groups. It is unlikely they were involved with the Islamists, Miyake said, but, he added, "perhaps they weren't discovered until now because they successfully blended and married into local society."

A spokesman for the MILF on Friday told The Yomiuri Shimbun: "I don't know the Japanese men in question. I've met men in the mountains who resemble Japanese, but I haven't confirmed whether they are Japanese."