Morinaga Milk Industry Co. held a memorial event Sunday for people who died after using powdered milk made by the company that contained arsenic, marking the 50th anniversary of the tragedy.

About 60 people, including Morinaga Milk President Koichi Furukawa, members of the victims' families and Health, Labor and Welfare Ministry officials gathered at Mount Koya in Wakayama Prefecture, where lists of the 951 victims are kept in a Buddhist temple.

"I believe we can prevent the memory of the incident from fading by appealing for food safety," said Yoshizo Obata, who heads a group of family members.

The incident took place between April and August 1955 when arsenic got mixed in with powdered milk at Morinaga's factory in Tokushima Prefecture, causing health problems for more than 13,000 people, mainly infants.