Published: Jun 29, 2011 4:53 PM EDT
Updated: Jun 29, 2011 3:54 PM EDT

SPRINGDALE, Ark. (AP) - One worker exposed to chlorine gas at a Tyson Foods Inc. chicken processing plant in Arkansas remains in intensive care and 13 others are still hospitalized.

Tyson spokesman Gary Mickelson said in an email to The Associated Press Wednesday that the number of hospitalized workers is down from about 50 Tuesday.

The workers were injured and the plant in Springdale evacuated Monday when two chemicals were accidentally mixed, creating the gas as a byproduct of a chemical reaction. Company officials say human error played a role in the accident.

A spokesman for the Occupational Safety & Health Administration says the agency has opened an investigation that could take up to six months.

Mickelson says a temporary medical clinic has been established at the plant and is staffed by a physician.

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