In June 1991, while filming eruptions at Mount Unzen (Japan), Katia went closer to the volcano and stayed longer during the eruption. Katia and her husband were caught in a pyroclastic flow which unexpectedly swept out of a channel where previously smaller flows had been following and onto the ridge they were standing on. They died along with 41 other scientists and journalists also covering the eruptions, several firefighters, and fellow volcanologist Harry Glicken.