A fire has broken out at an ExxonMobil oil refinery in Baytown, Texas, east of Houston. Local authorities have warned residents to close all doors and windows and turn off air conditioning as a precaution.

Emergency crews have responded to the Baytown Olefins Plant, assisting Exxon’s fire teams.

The company said it was conducting air quality monitoring “as a precaution” as well as “personal accounting” to ensure the safety of employees and contractors on the site.

“We deeply regret any disruption or inconvenience that this incident may have caused the community,” Exxon said.

Local residents sent video footage of flames inside the facility, which authorities say affected the unit that contains polypropylene material. The plume of black smoke could be seen for miles.

The City of Baytown is issuing a precautionary order to Shelter in Place due to an emergency at ExxonMobil Baytown Area. Areas west of ExxonMobil should Shelter In Place. See the map below. Please RT. pic.twitter.com/WWXOg3RpNf — City of Baytown, TX (@CityofBaytown) July 31, 2019

Soooo something just exploded in Exxon pic.twitter.com/PC4zvOSHjq — JBH (@B_MetalSucks) July 31, 2019

Three employees had suffered minor burns, according to local media. No other injuries have been reported. The cause of the fire is so far unknown.

Baytown Fire Dept official tells me 3 people have very minor burns after fire started at ExxonMobil Baytown Olefins Plant. Lots of workers are standing at the entrance waiting on their rides to pick them up. pic.twitter.com/l6viwzMlSS — Ivory Hecker FOX 26 (@IvoryHecker) July 31, 2019

This is the third fire at a petrochemical facility in the area in recent months. One person died in April when a tank holding flammable chemicals caught fire in Crosby, and a storage facility in Deer Park burned for several days in March.

Exxon describes the Baytown facility as “one of the largest integrated and most technologically advanced refining and petrochemical complexes in the world.”

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