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The Latest: South Philadelphia oil refinery fire
FOX 29's Lauren Johnson reports from South Philadelphia with the latest on the fire at local oil refinery, which shook homes before dawn Friday.
PHILADELPHIA - Authorities say a fire in a South Philadelphia refinery struck by explosions and a pre-dawn blaze last week has now been extinguished as an investigation is launched into what caused it.
Fire department and city officials said in a statement Sunday the blaze at the Philadelphia Energy Solutions Refining Complex was extinguished Saturday afternoon. Officials said the gas valve that had been fueling the blaze has been shut off and the tank involved in the explosion has been isolated.
Officials say the fire department's hazmat unit and the public health department are still monitoring air quality. No threat to public health has been reported.
Five workers were treated for minor injuries after the 4 a.m. Friday fire at a tank containing a mixture of butane and propane.
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Viewer video captures explosion at South Philly oil refinery
Viewer captures the explosion that turned into a three-alarm blaze at the refinery on Passyunk Avenue. (@1nicetownbean)
RELATED: Fire breaks out at South Philadelphia oil refinery after explosion
It's unknown whether the explosions will cause any financial strain the oil markets.
"This is obviously not a good thing to happen in a jittery market, but U.S. refined product demand has been relatively weak," said Jim Burkhard, vice president for oil markets at IHS Markit. "So this is a disruption, but it's probably not going to cause major problems in a market that is generally well supplied."
The Associated Press contributed to this report.