A LARGE explosion at an oil refinery has shot plumes of smoke into the air and left nearby residents seeking shelter.

Authorities have urged locals to stay inside as firefighters work to control the aftermath of the blast at the Valero refinery in Port Arthur, on the Texas coast.

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There has been an explosion at the Valero refinery in Port Arthur, TexasCredit: KFDM
 

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Locals reported hearing a loud boom before seeming the smoke plumes fro the refineryCredit: KPLCTV
The refinery is an estimated 90 miles east of Houston, according to Mayor Charlotte M. Moses.

Images of the blast have popped up online, showing large smoke clouds rising upwards from the plant.

Flames could also be seen billowing from the warehouse buildings.

Residents in the surrounding areas reported hearing a loud boom and seeing their windows shake.

Sheriff Zena Stephens said the explosion was likely caused by an industrial heater.

Despite this, officials have warned that the exact cause remains unconfirmed and under investigation.

There have been no reported injuries, however concerns remain over air quality as the fire at the refinery blazes on.

“There’s been an explosion, yes, but we’re OK; everybody’s OK,” Mayor Moses said.

“[Firefighters are] trying to put the fire out as quickly as possible.”

A shelter-in-place order has been issued for the west side of Port Arthur.

The City of Port Arthur has posted updated advice for locals on its Facebook page.

“For your safety please remain in place until the ‘All Clear’ is given by emergency personnel,” the statement said.

Texas state Representative Christian Manuel said the Texas Commission on Environmental Quality had arrived at the refinery with air monitoring equipment and was working with local and state partners.

In a post to social media he also urged residents to be cautious as the situation continued to unfold.

“Please limit outdoor activity, keep windows and doors closed, and follow guidance from local officials,” he said.

Authorities have also advised keeping doors and windows shut and avoiding outdoor exposure until further notice.

The explosion comes as global gas prices surge, driven by uncertainty over the world’s oil supply.

The refinery employs about 770 people.

It can process an estimated 435,000 barrels of oil every day, according to Valero’s website.

The plant plays a key role in producing essential fuels including heavy sour crude oil into gasoline, diesel and jet fuel.

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Firefighters are working to control the sceneCredit: AP
 

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Residents have been urged to stay inside as the situation continues to unfoldCredit: AFP