PHOENIX -- A pyrotechnics worker severely burned when an Independence Day fireworks display blew up prematurely in suburban Peoria died Monday, officials said.
Federal investigators searched for the cause of a blast hours before the start of the show at the Peoria Sports Complex that killed Michelle Galanda, 36, of Moorpark, Calif.Galanda was burned over 90 percent of her body and died at the Maricopa County Medical Center burn unit. Two fellow employees of Salt Lake-based Lantis Fireworks and Lasers were hospitalized with burns, and two others were treated and released.
Stacks of fireworks started detonating as employees were still unloading them at the complex, the spring training home of Major League Baseball's Seattle Mariners and San Diego Padres.
Lantis workers had dug several trenches and set up a big steel tube to hold the fireworks once they were hooked up to a control board, said Larry Bettendorf, a spokesman for the U.S. Bureau of Alcohol, Tobacco and Firearms.
"We believe they were working on the fireworks. The fireworks may have gone off right at their feet," he said.
A witness said he heard "50 to 60 explosions."
"I saw tons of white smoke filling up the baseball field and fireworks exploding along the ground. It sounded like the grand finale of a fireworks show," said Chris Powell, who was setting up his camera across the street to photograph the display.
Jeff Fraizer, 36, of Moorpark, Calif., was hospitalized in critical condition with burns on 60 percent of his body. Joyce Gyorwfy, 59, of Newberry Park, Calif., was in fair condition with less serious burns.
Company officials didn't immediately return calls to The Associated Press.
Lantis, which staged Peoria's Independence Day fireworks show last year, had planned to explode more than a thousand shells, Peoria fire spokesman Mike Tellef said. The show, expected to draw about 20,000, was canceled.
ATF bomb crews swept the fields Monday for unexploded fireworks. Bettendorf said many things could have caused the explosion, including static electricity, a spark or electrical malfunction.
Bettendorf was it was unlikely that the 100-degree heat contributed to the explosion, although the high temperature could have made the explosives more unstable.