UPDATE-- Investigators ruled the fire on 12th Avenue in Scranton as an arson.
Now, police want to speak with the owner of a truck found at the scene.
Police are calling Aureli Ceballos De Leon of Scranton a person of interest.
Witnesses tell Newswatch 16 shortly after hearing a loud explosion, they saw a partially dressed man running down 12th Avenue. Some say they saw the man holding his arm, or said he appeared to have been burned.
Ashley Conover lives down the street from the fire, "I see the guy running down the street in his underwear, and then I look up and see all the flames bursting from the top of the roof."
Firefighters say the loud explosion was likely caused by the gas line in the house igniting, and found the regulator had been blown off.
However, they say it does not appear the gas line was tampered with.
SCRANTON--Investigators are looking for the cause of an early morning fire in Scranton.
The first alarm at 321 12th Avenue came in just before 1:00 a.m. Saturday. It was quickly followed by a second. Firefighters found a home filled with flames, and those flames eventually shot through the roof.
Scranton fire officials tell Newswatch 16 one firefighter suffered an arm injury and should be okay. Firefighters' jobs were especially difficult because heat from the fire was setting off ammunition in the home. No one was hit.
Homes on both sides have fire, smoke, and water damage-- including melted siding.
Firefighters were on the scene for hours. Several roads in west Scranton were closed. Smoke covered a big portion of the city.
The fire was declared under control a couple of hours after the first alarm came in.