Wires

UPDATE 1-Exxon fighting fire at Baytown, Texas, refinery

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HOUSTON, July 31 (Reuters) - A fire broke at Exxon Mobil Corp's 560,000 barrels per day Baytown, Texas, refining and chemical plant complex on Wednesday, said the company and local officials.

Exxon asked local residents around the plant to shelter in place, according to a Baytown emergency management official. Baytown is a city of 75,000 people about 30 miles (48 km) east of Houston.

The fire, which was being fought by the company's employees, sent black smoke into the air over the complex in the Houston suburb.

Local television footage showed a flames and heavy smoke from a large column at the facility, which Exxon identified as part of its olefins production. Officials said the fire was in a unit that contains polypropylene material, a component of plastics.

Exxon said in a tweet that it was conducting air quality monitoring at the facility. It was in the process of accounting for employees, the tweet said. (Reporting by Erwin Seba Editing by Marguerita Choy)