Chief Cabinet Secretary Shinzo Abe said Thursday he received a letter from someone in Hong Kong earlier in the day that he claimed threatened his life if he visits Yasukuni Shrine.
The letter, posted in Hong Kong July 3, said in Japanese: "Don't visit Yasukuni! If you visit, you will be punished by heaven!" The letter contained a 10 cm-long box cutter blade.
Abe's office said it immediately notified police.
Abe, who is known for his patriotic views and tough stance in disputes with China and South Korea, is widely believed to be the leading candidate to become prime minister after Junichiro Koizumi steps down in September.
Since Koizumi took office in 2001, his annual visits to the war shrine have sparked criticism in other parts of Asia, particularly China and South Korea, which suffered from Japan's wartime invasion and occupation.
"Such a letter will not influence my actions," Abe said.
The letter was addressed to the Cabinet Office in Chiyoda Ward, Tokyo.
A Chinese name and a Hong Kong address were written on the back of the envelope.
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