Police late Sunday found a car doused with what appeared to be gasoline in the parking lot of the local office of the General Association of Korean Residents in Japan (Chongryun), a pro-Pyongyang organization.
Police were alerted to the incident when a man called claiming to have committed the act, police officials said Monday.
The call came in at around 11:40 p.m. Sunday. Around the same time, Kyodo News received a call from a man claiming to be from a group he called Nippon Kofugun (Japan Imperial Grace Army). He said he poured gasoline on the car and set it ablaze in a bid to "face down" North Korean leader Kim Jong Il.
The apparently middle-aged caller told the wire service's Tokyo headquarters that his act was aimed at preventing Kim from abducting people and at maintaining public order in Japan.
Following the call, Oita Prefectural Police investigators rushed to Chongryun's Oita prefectural headquarters, where they found a car in the parking lot that had been apparently doused with gasoline, the officials said.