A screen grab from the video shows people being trapped by flames. [Photo/IC]

TAIPEI - Investigators in Taiwan were focusing Monday on the possibility that a cigarette butt or spark caused the blaze that killed one and burned nearly 500 people at a weekend water park party when colored powder sprayed from the stage caught fire.

The 20-year-old woman, surnamed Lee, suffered burns to 90 percent of her body, according to Chung Shan Medical University Hospital in the island's Taichung City. This is the first fatality in the tragic accident.

More than 400 people remained hospitalized, 200 in serious condition, city officials said. Eight suffered life-threatening injuries, local media said.

Police recommended criminal charges against the organizer of Saturday's party, as well as two technicians, at the theme park in suburban Taipei.

"It's still not clear what happened, but there were a number of people smoking and the weather was warm," New Taipei City news department head Lin Chieh-yu said. Temperatures around Taipei topped 36 degrees Celsius (96.8 F) before the party.

The three tons of colored starch-based powder bought by the organizers from Tai Won, a seller in the island's southern county Yunlin, were flammable, said Chou Hui-fang, a representative of the seller. She said the buyer was informed about the risk of fire.

"Whether it's corn starch or flour starch, this kind of stuff, no matter how long it's been around, if it's in dense quantities and if it's hot, it can catch fire," Chou said. She said her 4-year-old company has been questioned by police and health officials but not considered at fault.

"We didn't know what the buyers were going to do with it or how much they would use," she said. "It might have been supplies for a whole year."

Taiwan's chief administrator Mao Chi-kuo on Sunday announced a ban on colored powder at future private events. The water park was ordered to close after the fire.

Colored powder is often thrown on revelers during the annual Holi celebrations in India and Nepal, a Hindu festival, but the powder at Saturday's party was made in Taiwan, Chou said.