TAMPA, Fla. (AP) -- As flames shot through the roof of a million-dollar home, neighbors reported explosions, presumably hearing fireworks go off inside the house as it burned down with a family of four inside.
Authorities called the fire arson and said they were investigating a possible murder-suicide, but they haven't indicated who may have started it or why. The man renting the home with his family, Darrin Campbell, bought $650 of fireworks days before the blaze and the fireworks were found throughout the five-bedroom home. Still, it wasn't clear what role, if any, fireworks might have played in the Wednesday morning fire.
Campbell, his wife and their two teenage children were found dead inside. Police were performing autopsies to determine how they died.
Campbell had been an executive for several high-profile businesses. He was currently working at a records management firm and volunteering as treasurer at his children's private school. His wife, Kimberly, was a stay-at-home mom, according to her father, Gordon Lambie.
The family moved to Tampa more than a decade ago. They sold their home in 2012 for $750,000 and moved closer to their children's school, Carrollwood Day School, Lambie said.
Nineteen-year-old Colin Campbell was a talented baseball player who planned to graduate high school next month. His teenage sister, Megan, was a ninth-grader who made an honor roll and took dance lessons.
"I've lost my entire family," Lambie said from his Michigan home. "It's very tough right now because I'm 1,500 miles away."
Hillsborough County Sheriff's Col. Donna Lusczynski said an accelerant was used, but she didn't say what it was.
Two victims suffered upper-body trauma, but Lusczynski didn't indicate which ones or provide other details. No weapons had been found, she said.
Campbell bought six packages of firecrackers and about the same number of aerial fireworks designed to shoot into the air, said William Weimer, vice president of Ohio-based Phantom fireworks. He described them as backyard fireworks someone might set off on the Fourth of July.
He said the fireworks could have started a fire but it would have spread slowly. The amount of powder inside each one of them was smaller than an aspirin, he said. A store manager, Rocky DiRoma, said there was nothing unusual about the $650 purchase.
"He was just an average Joe," DiRoma said.
Neighbors described hearing the fireworks.
"Geez. What is that popping noise?" a man said on a 911 call.
Another 911 caller, a security manager for the gated community, told dispatchers the fire was in the garage.
Darrin and Kimberly met in Lansing, Michigan, when they both worked as aides in the state legislature, her father-in-law said. Kimberly Campbell had graduated from Central Michigan University and Darrin Campbell had an MBA from the University of Michigan.
They lived in San Antonio, where Campbell was an executive with Pearl Brewing Company, before moving to the Tampa area around 2001.
At some point, he became senior vice president at PODS, the mobile storage company, and left there in 2007.
Darrin Campbell was currently chief operating officer at Vastec, and had worked there for the past six months.
They signed a two-year lease for a home owned by former tennis star James Blake and moved in at the end of 2012. Blake bought the 6,000 square-foot home in the Avila subdivision in 2005 for $1.5 million, according to property records.
Avila is known for its mansions, heavy security, country club and golf course. Many well-known athletes have called the community home over the years.
Friends of the teens gathered Wednesday and released balloons with messages on them as a remembrance.
A former neighbor, George Connley, said Kimberly Campbell was "sophisticated and classy."
"We know nothing of any problems," Connley said. "The kids were outstanding children. This is very difficult to put our arms around."
Schneider reported from Orlando.
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