(Adds victims were found with gunshot wounds, background)
MIAMI, May 8 (Reuters) - A family of four suffered gunshot wounds before they died in a blaze that destroyed a Florida mansion owned by former professional tennis player James Blake, police said on Thursday.
Detectives were still working to identify the people and determine the cause of Wednesday's fire, said Debbie Carter, a spokeswoman for the Hillsborough County Sheriff's Department.
Authorities have not ruled out the possibility the fire may have been a murder-suicide and investigators said they found fireworks throughout the house.
The father of the family who rented the home purchased a large amount of fireworks and several gasoline cans at a home improvement store days before the fire, Carter said.
The police have said they are not pursuing any suspects in the blaze and have yet to identity the four people who died.
Blake was renting the more-than-6,000 square foot Tampa home and was not in the property when the fire broke out.
In a statement on Thursday, Tampa technology company VASTEC identified the victims as Darrin Campbell, the firm's chief operating officer, and his family, TV station WFTS reported. A VASTEC official could not be immediately reached for comment.
The Hillsborough County Sheriff's Office said two male and two female bodies were found inside the house. Two of the bodies showed signs of upper body trauma, but officials did not immediately provide additional details.
The Tampa Bay Times reported that Campbell purchased some $600 worth of fireworks on Sunday.
William Weimer, vice president of Phantom Fireworks, told the Times that surveillance footage showed Campbell bought six packages of small firecrackers and seven packs of aerial fireworks designed to shoot into the sky.
"There was nothing about the transaction itself or the products he purchased that would be out of the ordinary," Weimer said. "You'd probably purchase more to shoot off on the Fourth of July."
Authorities received a call to 911 reporting an explosion and fire at the home at 5:45 a.m. Wednesday.
"I was walking my dog and the house just exploded," the caller said. "The house is engulfed in flames." Police released a recording of the call.
Blake, 34, retired from professional tennis in 2013. He bought the five-bedroom, five-bathroom house for $1.5 million in 2005, according to Hillsborough County property records. (Reporting by Kevin Gray; Editing by Grant McCool and Richard Chang)