Several hundred marijuana plants were found in the ruins of a house gutted by fire in Maebashi, Gunma Prefecture, on Jan. 15, investigative sources said Wednesday.
Police suspect the house was used for a cannabis-growing operation and are searching for people who were regular visitors, the sources said.
According to a neighbor, the house had been shuttered all day long since around October 2007, and a lot of people would come and go at the premises. Neighbors were told they were involved in the recycling business.