We reported earlier this month on a truly weird case unfolding in Japan: Someone is sending threatening letters to venues connected to the manga and anime Kuroko's Basketball, including convention centers that host doujinshi (fan comic) events, bookstores that sell the manga, and Sophia University, where creator Tadatoshi Fujimaki attended school. Some bookstores have removed the manga, and convenience stores, including 7-Eleven, also pulled Kuroko's Basketball-themed snacks after receiving letters saying they had been poisoned.

There were two developments in the case last week. The first was that a small amount of nicotine was found in one of the recalled snacks; the package appeared to be "suspiciously" sealed. However, investigators said the amount found was 1/100th of a lethal dose.

The other other was that Tokyo police announced they may have security camera footage of the suspect — and, in fact, they may have questioned him more than a year ago.

In early October 2012, police questioned a man dressed in black at a railway station near Sophia University. Later, a person claiming to be the sender of the threat letters posted on an online message board, "When I put the container in a coin-operated locker at Yotsuya Station, I was questioned by police." Police believe the suspect is the person they interviewed.

Then, on Oct. 12, 2012, someone left a potentially lethal amount of hydrogen sulfide in the university's gymnasium. A security camera on campus caught images of a thin man dressed in black and carrying a container; several students reported seeing him as well. The man's face was hidden from the camera, but again, police believe he is the person who has been sending the threatening letters.

Meanwhile, an important date connected with the threats passed without incident: Sophia University officials received a threat letter saying that "X-Day" would be the last day of their school festival, Nov. 4. The Japanese television station TBS reported that about 250 threat letters were received in October by both retail stores and news organizations; the one sent to the Tsutaya rental chain (which has removed the books and videos from its shelves) contained lighter fluid, and the one sent to the daily paper Sankei Shimbun said "I will go to bookstores that sell Kuroko volumes and completely burn them down."

(Image of Kuroko's Basketball snacks came from this post at Anime News Network.)