Ignoring protests at home and abroad, Prime Minister Junichiro Koizumi visited a shrine memorializing Japan's war dead Tuesday, and a few hours later a possible arson fire burned down the home and office of a lawmaker who has criticized the leader's pilgrimages.

Koizumi went to Yasukuni Shrine on the anniversary of Japan's World War II surrender to fulfill a 2001 campaign promise, shrugging off several days of demonstrations in Tokyo by those who feel the shrine glorifies Japanese militarism and complaints from China and South Korea.

The visit further strained ties with the neighboring nations already driven to their lowest point in decades by Koizumi's earlier visits to Yasukuni and a host of spats over territory, natural resources and other issues.

CountryWatch: Japan

Koizumi, however, is scheduled to leave office at the end of September, which means his successor — likely Chief Cabinet Secretary Shinzo Abe — will start his term with fresh diplomatic troubles on his hands.

"It was a self-righteous decision," said Yoshinori Murai, a political scientist at Tokyo's Sophia University. "Japan will be isolated if it shows it doesn't care about criticisms from home and abroad."

The shrine honors Japan's 2.5 million war dead, including executed war criminals from World War II. Many in Asia see Koizumi's visits as proof Japan has not atoned for its past aggression.

The impact of the visit was heightened by its timing on Aug. 15, a date viewed with sadness in Japan as the anniversary of its World War II surrender, but celebrated as a day of liberation from Japanese colonial rule elsewhere in Asia.

The angry response from China and South Korea was swift.

"On behalf of the Chinese government and the Chinese people, I express strong indignation and severely condemn" the visit, Chinese Foreign Minister Li Zhaoxing told Japanese Ambassador Yuji Miyamoto in Beijing.

South Korean President Roh Moo-hyun called on Japan to "prove it has no intention to repeat" its past aggression as his government summoned the Japanese ambassador to issue an official protest.

Koizumi defended the visit — his sixth to Yasukuni since 2001 but his first on Aug. 15 as prime minister — by saying he goes there to pray for peace and to honor fallen soldiers, not to celebrate militarism. Dozens of lawmakers also prayed there Tuesday.

"I don't go there to repeat the past war and justify the war," he told reporters after the visit. "We should not forget the sacrifices made by those who fell for the country."

Koizumi accused China and South Korea of using the issue to pressure Japan on other issues. Leaders of both countries have refused to meet with Koizumi unless he stopped the pilgrimages.

His pilgrimage drew praise from some Japanese war veterans and rightists who argue the country's leaders should have the right to honor the war dead as they please.

A fire late Tuesday destroyed the adjoining house and office of lawmaker Koichi Kato, a member of the ruling Liberal Democratic Party who made numerous TV appearances during the day criticizing Koizumi for his shrine visit.

Investigators were still looking into the blaze but arson "could not be ruled out," police official Koji Suzuki said.

An unidentified man was found collapsed on the grounds with wounds to his abdomen and was taken to a hospital, Suzuki said. It wasn't immediately clear whether the man was suspected of setting the fire and police declined to release additional details on the man's injuries.

Koizumi's latest visit to the shrine comes amid Japan's efforts to take a more assertive role in the world.

His administration has sent non-combat troops to Iraq, moved to change its constitution to allow more military action overseas, and launched a determined campaign to win a permanent seat on the U.N. Security Council.

But while Japan's military and diplomatic ties with its top ally, the United States, have prospered, its relations with Asian neighbors have deteriorated. Anti-Japanese protests flared up last year in several Chinese cities.