A drone. Image: Wikimedia.

For the foreseeable future, the Tokyo Metropolitan government has banned hobbyists from flying drones in public parks following a strange protest against nuclear power targeting the Japanese prime minister.

The ban on drones in Tokyo public parks, which came into effect on April 28, comes after a drone carrying trace amounts of radioactive substances was discovered on the roof of the prime minister's official residence in central Tokyo on April 22.

Yasuo Yamamoto, a native of Obama in Fukui Prefecture, told police he was responsible for piloting the drone, and that the drone, with its payload of radioactive soil, had sat undetected on its rooftop location for nearly two weeks before being discovered. It also appeared that Yamamoto had carefully painted the drone black to avoid being spotted easily.

Yamamoto turned himself in to the police on April 24, and was formally indicted on Friday, May 15.

Since his arrest, Yamamoto has become known online as the “drone otaku” (drone geek) or “drone ojisan” (middle-aged drone guy).

ジャックログ : 【マジキチ】出頭したドローン放射脳おじさんのブログがヤバいｗｗｗｗｗｗｗｗ http://t.co/yRy4bg0pNV pic.twitter.com/59URVrnAht

— ジャックログ (@2chjacklog) April 24, 2015

On the Jack Blog: This Is Craaazy (majikichi, マジキチ): Loony no-nukes drone guy Yasuo Yamamoto has a blog and it is NUTS.

The fact that the Tokyo Metropolitan Police Department (警視庁, keishicho) is responsible for providing security for the prime minister's residence presumably influenced the decision to effectively ban drones in and around Tokyo.

However, while drones are banned from public parks in Tokyo there are no laws regulating the use of drones themselves, particularly near public buildings such as the National Diet or the Imperial Palace in central Tokyo.

Yamamoto said that his stunt was intended to be a protest against Japan's nuclear energy policy. He was indicted for interfering with official duties on May 15.

Yamamoto told investigators he had not intended to commit a terrorist act, but instead wanted to raise awareness of Japan's nuclear power policies by using a drone, which he regarded as being trendy and high-profile.

He also claimed the radioactive soil, which investigators confirmed contained traces of cesium, a long-lived radioactive isotope that was a by-product of the 2011 accident, came from Fukushima Prefecture.

Fukushima Prefecture was the scene of Japan's worst nuclear accident in March 2011. Widespread radioactive contamination forced thousands to be evacuated from Fukushima prefecture and sparked a strong and ongoing anti-nuclear protest movement in Japan.

Obama Port; the Ohi nuclear power plant is just on the other side of the peninsula. Image credit: Nevin Thompson

Yamamoto comes from the small city of Obama in Fukui Prefecture. Fukui is home to the largest concentration of nuclear reactors on earth, and the Ohi nuclear power plant is located almost within sight of downtown Obama.

He also until recently had worked at the Sendai nuclear power plant in the southern prefecture of Kagoshima.

The Sendai plant has been in the news this spring after Kagoshima District Court rejected a bid to block it from restarting.

Following Yamamoto's confession and arrest in late April, Japanese netizens were quick discover that he maintained a blog, and that he also uploaded original manga, or comics, to the Internet.

【漫画家だったの!?】官邸ドローン事件の山本泰雄容疑者が漫画を描いていたことが判明ｗｗ http://t.co/gIBZtT4v7K　’ｗ）ドローン塗装もパーツから分解して塗装したり、方向を確認するためのライトを塗りつぶしたりしてる時点で性格はかなりﾏﾒで手先器用だと理解してたが — ura (@uraurx) April 26, 2015

Tweet reads: He was a manga artist! It has been revealed that Yasuo Yamamoto, who landed a drone on the roof of the prime minister's residence, is also a manga artist. It helps explain how he was so fastidious in taking apart the drone to paint every single last piece black.

Quoted below: Yasuo Yamamoto is a manga artist. While the themes may be brutal if you feel that you absolutely must check it out, all you have to do is sign up and you can read his manga for free on the Internet. Following his drone stunt, Yamamoto has been arrested on suspicion of interfering with official duties. This is what he says is his blog.

Based on his blog, the online consensus in Japan is that Yasuo Yamamoto is most likely not a bona fide nuclear protester but is instead a bit of an eccentric.

Japanese netizens, however, have found his manga, available for free online, irresistible.

官邸ドローン事件の山本泰雄の描いた漫画が凄過ぎる！いろいろな意味で – 夕日新聞 http://t.co/2t1yOTJ6yu #news @yuuhinewsから

— 夕日新聞 (@yuuhinews) April 27, 2015

Here's the manga created by Yasuo Yamamoto, the man suspected of landing a drone on the roof of the prime minister's residence. It's totally amazing, in a variety of ways. – Yuuhi Shimbun.

Caption: HELLO WORKER

Caption below: Yasuo Yamamoto uploaded his own original manga to manga-sharing site Nico Nico Manga. Yamamoto's manga is called “HELLO WORKER” and has become a hot topic online. While the themes are unsettling, Yamamoto's drawing style is compelling.

Yamamoto's manga is disconcerting to read, but makes for absorbing reading.

官邸ドローン事件、山本泰雄容疑者は漫画家志望だった？ 容疑者描いた漫画が面白いと話題に http://t.co/Wg5bk98YL0 :２ろぐちゃんねる #2ちゃん #まとめ #2ch pic.twitter.com/p7vb1tUUTm

— ２ろぐちゃんねる (@2log_ch) April 27, 2015

Did Yasuo Yamamoto dream of becoming a manga artist? Yamamoto's manga is compelling and has become a hot topic.

The tweet above links to a summary of a 2chan discussion that features extracts from Yamamoto's manga, followed by a long discussion thread. 2chan is Japan's largest online community, similar in size, scope and tone to Reddit.

Yasuo Yamamoto's drone exploits have also caught the attention of famed director Mamoru Oshii. Oshii, whose popular movies include cyberpunk classic Ghost in the Shell, has long explored how humans interact with technology.

In an interview with movie news site eiga.com, Oshii said:

「あれが出てきた瞬間に、テロの有効手段だと思った。撮影でも使ったし、現場でも“これに爆弾をつるせないか”という話もしていた」と大胆発言。そして、「映画はウソだからいいけれど、今は現実の方が先にいっているから、やりにくいといわれればやりにくい」

As soon as I heard what happened at the prime minister's residence, I thought drones could be an effective weapon for terrorists. I myself have used drones on film shoots, and when on location I've thought, “You know you could deliver a bomb with a drone.” While movies are make-believe, what used to be fiction is now becoming closer to reality.