YAMAGUCHI (Kyodo) The carbon monoxide that killed a 26-year-old man and injured school kids, teachers and others at a hotel in Yamaguchi Prefecture may have been caused by a leaky boiler chimney in the basement, investigative sources said Wednesday.

Photographer Hiroaki Kawazoe, 26, died of carbon monoxide poisoning at the Yamaguchi Shuhou Plaza Hotel. He was covering a field trip for an elementary school from Takatsuki, Osaka Prefecture.

Other people sickened by the gas, including several children, were taken to area hospitals.