Over the weekend, the fire department in Osaka, according to NHK, Japan’s public broadcaster, began emergency on-site inspections of buildings with only one set of stairs, identifying close to 5,500 such structures in the city of nearly 2.7 million. The fire department checked to make sure these exits were not blocked.
Two years ago, another arsonist in an anime studio in Kyoto, not far from Osaka, killed 33 people and wounded dozens in one of Japan’s worst massacres in decades. In that case, fire experts identified several problems with the building, which also had only one main staircase and lacked fire protection on interior fixtures.
Such incidents disrupt a basic sense of security in Japan, where crime is relatively rare and the murder rate is among the lowest in the world.
“In Japan, there is a myth about security,” said Yasuyuki Deguchi, a criminal psychologist at Tokyo Mirai University. “Stopping these crimes is very, very difficult,” he added. “Most of these crimes happen without any warning. You can not even guess that they are thinking of arson.”
Experts in arson say it is a public health problem where many perpetrators show signs of mental illness. Theresa A. Gannon, a professor of forensic psychology at the University of Kent in England, said arsonists were often antisocial or had trouble forming intimate relationships, and that they used arson as a coping mechanism or to gain attention.
Ms. Gannon and a team at the University of Kent have developed a training program for mental health professionals to treat people who have previously set fire. She said the team had trained professionals in the United States, Australia, Canada and Singapore, and that a manual was available in Japanese.
Last year in Japan, there were nearly 2,500 arson incidents that killed 236 people, according to the Fire and Disaster Management Agency.