SOUTH PHILADELPHIA - Fire officials say the blaze that engulfed Philadelphia Energy Solutions complex Friday morning is contained, but not under control.
Deputy Fire Commissioner Craig Murphy said the contents of the tank are still burning and will continue to burn until Philadelphia Energy Solutions workers are able to safely shut off a main valve.
"It's not safe with the fire still burning for them to get to where the valve is to shut this thing down," Murphy said.
The main valve needs to be shut off before the fire is extinguished to ensure that harmful chemicals do not leak into the atmosphere.
The fire, which was sparked by an explosion at the plant, happened around 4 a.m.
Fire officials say the fire started in a vat of butane that eventually exploded. A series of smaller explosions happened as the fire worked its way through the tangle of pipes carrying fuel across the complex.
Murphy confirmed there were several minor injuries.
It's the second fire at the refinery in one month, following a June 10 fire in which no injuries were reported.
A temporary 'shelter in place' order was given to nearby residents and multiple SEPTA bus routes were diverted.
The complex produced 335,000 barrels of crude oil daily. Philadelphia Energy Solutions says the oil refining complex is the largest on the U.S. Eastern Seaboard.
The Philadelphia Department of Public Health took to Twitter to alert residents that air samples determined there was no further threat to the surrounding community.
The Associated Press contributed to this report.