Updated 08/28/14 – 6:08 a.m.

(CBS) — An explosion occurred at the BP Whiting, Ind., refinery Wednesday night.

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A Whiting Fire Department spokesman said the explosion, at about 9:05 p.m., could be heard clearly several blocks from the plant. But the spokesman said that when Whiting Fire commanders called the plant to ask if their assistance was needed, they were told only to stand by and that BP was handling it internally with its own fire department and ambulances.

People as far as two miles away reported feeling the explosion.

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BP spokesman Scott Dean confirmed the refinery experienced “an operational incident on a process unit on the north end of the refinery.”

The refinery’s in-house fire department extinguished the fire by 11 p.m. One employee was taken to the hospital as a precaution, but was later released.

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The explosion Wednesday night comes exactly 59 years after a massive fire at the refinery, then known as the Standard Oil Refinery. Two people were killed, and the surrounding neighborhood was devastated by the fire.