The authorities tracked down each person who had custody of the painting, "and we finally secured a statement from the last person that he donated it to a temple in Daegu," prosecutors said.

Temple officials admit that they received the painting, but they have refused to hand it over to the authorities for further investigation," the prosecutors said.

On Tuesday, the authorities conducted an intensive search of the temple with the temple's permission, but were unable to find the painting. Now the prosecutors are looking into the possibility that monks at the temple may have hidden the painting for fear the national historic asset might be sent back to Japan - which many Koreans consider sending it to the hands of the 'looters.'

The Amitabha Triad, which shows three Buddha figures, has an estimated value of 1 billion won, nearly $1 million. Until it was brought back to Korea, it was one of 106 Buddhist paintings from the Goryeo Dynasty believed to scattered in temples, museums and elsewhere in Japan. In Korea, only 13 other paintings from Goryeo, which lasted from 918-1392, are known to exist.

How the hundred or more Goryeo paintings ended up in Japan needs to be studied. It is widely believed, however, that many were looted by the Japanese during their past invasions of Korea, including the 1592 invasion by Hideyoshi and the 1910-1945 Japanese colonial rule of Korea.

The paintings are part of a large number of Korean treasures that are widely believed to have been stolen by the Japanese. According to the Korean Heritage Administration, there are more than 34,000 Korean historic artifacts in Japan.

It is against this backdrop that some Koreans have begun to question whether the treasure, although it was stolen in Japan and smuggled into Korea, should be returned to the Japanese temple, or whether it should remain in Korea.

Experts and prosecutors say it is unlikely that the painting will be returned to Japan since none of the last few owners appear to have been aware they were buying something that was stolen.

According to the investigators, the last owner of the painting was a Buddhist, who received it from a business partner as a token of gratitude for an investment. The Buddhist later donated it to the temple in Daegu.

The business partner reportedly purchased the painting from someone else for 400 million won, believing it was from North Korea.

"The property in question belongs to a private owner - the Kakurinji temple - not the Japanese government. Once the court rules it should remain with the bona-fide Korean owner, that's it. There should be no diplomatic complications regarding restitution," Lee Hong-hun, the chief prosecutor in charge of the case, told The Korea Herald.

"The Japanese owner can still file suit in a Korean court and attempt to argue that the owner was aware at the point of the purchase," that he was buying stolen goods, he noted.

According to Article 249 of Korean Civil Law, a bona-fide owner is entitled to claim a possessive right over stolen goods. Lee said the same principle applies under Japanese law.

Two men accused of stealing the painting in Japan, Kim, 55, and Hwang, 53, were arrested by Seoul police last month after a 3-month collaborative probe by Korean and Japanese investigators.

Apparently motivated by avarice mixed with distorted patriotism, the two went over to Japan and conducted a cultural acquisition tour from 1998 to 2000, allegedly stealing 47 cultural and historic items from Buddhist temples. The estimated value of all 47 items tops 4.5 billion won, according to the police.

Among the items were six Buddhist paintings from Goryeo Dynasty including the Amitabha Triad, and a painting of a Buddhist Mandala from a temple at Aichi on Honshu. The pair allegedly smuggled the paintings into Korea.

"We believe the Korean authorities will do whatever is necessary and take due procedures to restitute the stolen assets," an official at the Japanese embassy in Seoul told The Korea Herald.