TOKYO - A novice Japanese lawmaker lambasted by critics for breaching imperial etiquette has received a death threat in an envelope that contained a knife, reports said Wednesday.
The menacing letter, discovered by security officers at a Tokyo building filled with lawmakers' offices, warned that "a group of assassins will be dispatched shortly", public broadcaster NHK and other media reported.
Inside the envelope was a clasp knife with a nine-centimetre (3.5 inch) blade, Jiji Press news agency said.
The threat was directed at actor-turned-politician Taro Yamamoto, who was elected to parliament as an independent on a strongly anti-nuclear platform.
The lawmaker caused outrage by handing a letter to Emperor Akihito during a royal garden party last month, which some critics say was a breach of protocol since the revered figure is seen as being outside the political fray.
Yamamoto has said the hand-written note had been his attempt to let the emperor know directly about the plight of people affected by the atomic disaster at Fukushima.