Officials found the four bodies around 2 a.m. Tuesday after getting an alarm call from a home in Tarpon Springs.
Police Capt. Jeffrey Young says the incident may be related to an early morning fire at a gun shop about a mile away.
The fire at Silver Bullet Guns set off a string of explosions as ammunition caught fire, forcing authorities to shut down a street.
Police say they're waiting on positive identification and notification of relatives before releasing the victims' names.
Investigators from the Pinellas County Sheriff's Office and the State Attorney's Office are assisting Tarpon Springs police investigators. Officials from the medical examiner's office were also at the scene early Tuesday morning.