At least 60 people, including small children, were rushed to hospitals Thursday evening in Fukuchiyama, Kyoto Prefecture, after a propane tank apparently exploded in a food stall just before a major fireworks festival was to start, police and rescue workers said.

The blast, which took place at around 7:30 p.m. at the event venue along the Yura River, reportedly caused two women in their 40s to suffer severe burns over their entire bodies.

The blast came just before the fireworks event began, and the event was immediately canceled, its organizer said.

Witnesses said the blast left just the frame of the food stall standing. Strewed about the site were sandals, PET bottles and other belongings.

The annual Dokkoise Fukuchiyama Hanabi Taikai fireworks festival was slated to display about 6,000 fireworks over a 90-minute period. The annual mid-August event during the Bon holidays draws hundreds of thousands of people.

Police are investigating the cause of the blast.