Nine people are injured, four of them critically, after a number of explosions at a Blue Rhino Propane plant in Tavares. The first explosions were reported around 10:38 p.m. on Monday.
FOX 35 viewers said they heard the booming sound of the explosion up to 10 miles away.
Officials say 24 workers were at the plant at the time. All were accounted for early Tuesday after officials initially couldn't locate more than a dozen.
The federal Occupational Safety and Health Administration launched an investigation, as did the Florida State Fire Marshal's office.
One person injured in the explosion was listed in critical condition at University of Florida Health Shands Hospital and three others were listed in critical condition at Orlando Regional Medical Center. Lake County Sheriff's Office spokesman John Herrell said some others drove themselves to area hospitals.
Tavares Fire Department Battalion Commander Eric Wages said five workers walked up to a command center firefighters set up near the plant Monday night with skin hanging off their arms, torso and faces. He said their arms were outstretched and they were in complete shock.
The Blue Rhino plant, which is northwest of Orlando, is stocked with 53,000 20-pound propane tanks, the kind used for backyard grills. Workers fill and stack the tanks at that facility.
"They also have three bulk cylinders," said Tavares Fire Chief Richard Keith. "Those bulk cylinders hold around 90,000 pounds of propane. The bulk cylinders, thank goodness, did not ignite. They are safe."
Fire officials say it appears workers were on the assembly line when the fire broke out and someone hit an emergency stop button. It's not clear what caused the initial explosions.
"We don't think that there was any act of sabotage or anything like that," said Chief Keith. "We honestly think it was probably an equipment failure with a combination of maybe a human error from one of the staff."
One of the injured people was hit by a car trying to run across the road.
The Florida Highway Patrol confirmed that 29-year-old Leesburg resident Kaghy Sam was struck by an SUV driven by 72-year-old Gene Batson on a road near the Blue Rhino plant.
A statement from the FHP to The Associated Press said that Sam was running on the road "due to a large fire and several explosions" just before 11 p.m. Monday and "ran into the direct path" of Batson's vehicle.
Sam was flown to Ocala Regional Medical Center with serious injuries.
No charges were filed in the accident.
Blue Rhino is a subsidiary of Kansas-based national propane provider Ferrellgas. Spokesman Scott Brockelmeyer said Tuesday he didn't have information available about the safety water hoses.
"It's as sobering a situation as you can possibly imagine," Brockelmeyer said. "We have folks who are injured, and we've got Blue Rhino and Ferrellgas employees across the country who are keeping them in their prayers and sending good vibes their way."
Brockelmeyer said there were 14 full-time employees and 10 part-time workers in the plant when the explosions occurred Monday night.
Ferrellgas did pay a $2,295 fine in November 2011 following an OSHA inspection that found a component at the end of an air hose used in the consumer tank refurbishing process was not present.
Brockelmeyer said the company corrected the issue and added that "the process is performed in area away from where the tanks are filled....so no product was being processed in that area."
The explosion rocked nearby neighborhoods. Herrell said about 50 homes were evacuated Monday night but residents were allowed back in about four hours later.
Marni Whitehead, 33, who lives less than a mile from the plant, said she was in bed ready to go to sleep when she heard a loud boom.
She ran outside and saw other neighbors outside and then they saw the explosions.
"We knew right away it was the plant, the propane plant," Whitehead said. "After that, it was just sort of panic."
Whitehead likened the explosions to Fourth of July fireworks. "And it was just boom after boom after boom," she said.
Smoke still billowed on Tuesday morning from a storage container on the property, which consists of a couple of warehouses next to each other. The parking lot was littered with thousands of blackened 20-pound propane containers.
"The State Fire Marshall's office, Lake County Sheriff's Office, and the City of Tavares Police Department will be working in unison to help us determine that final cause," said Chief Keith.
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Some information taken from wire sources including the Associated Press.