The fire broke out after a possible explosion at the refinery where crude oil in broken down into various components so it can be turned into gasoline or petroleum coke, the (Gulfport, Miss.) Sun-Herald reported.
"Refinery teams responded, the site is secure and there is no danger to the community," said Alan Sudduth, spokesman for Chevron in Mississippi.
Sudduth confirmed that one person, only identified as being a Chevron employee, was killed in the incident, and that there were no other injuries.
"We're not releasing anymore information at this time," Sudduth said. "It's a little too soon."
Jackson County Emergency Services Director Earl Etheridge said he was unable to confirm reports of an explosion, but "we had a number of people in Pascagoula report it as an explosion. That's still being looked at."
The incident comes just a day after a Chevron pipeline exploded and caught fire in rural Texas. No injuries were reported in the Thursday incident.