Arson was the main cause of fires in 1999 for the third successive year, with 7,481 cases, according to an annual government white paper endorsed Tuesday by the Cabinet.
This marked an increase of 187 arson cases over the previous year.
The report, presented before the Cabinet meeting that day by Home Affairs Minister Toranosuke Katayama, says confirmed cases of arson account for 12.8 percent of the fire disaster total, with the figure moving up to 22.1 percent should suspected cases be taken into consideration.
According to the report, the total number of fires in 1999 was 58,526, up 4,012 from the previous year.
The second-largest cause of fire was from cigarettes, with 6,415 cases -- up 725 from the 1998 figure.