CRESSON (CBSDFW.COM/AP)A fire at a North Texas chemical plant following an explosion last week is being allowed to burn itself out before authorities search for a missing worker who’s presumed dead.

Cresson Mayor and Assistant Fire Chief Bob Cornett said Sunday that conditions at the 15,000-square-foot Tri-Chem Industries plant are “just too hot” and “just too dangerous.” He says rains Saturday night aggravated chemicals and acids at the site about 25 miles  southwest of Fort Worth.

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Cornett says the plant is being guarded to ensure no one enters and that state and federal environmental and workplace officials are standing by to assist local authorities.

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According to the Hood County Fire Marshal, rescuers have performed a number of searches looking for 27-year-old Dylan Mitchell, but they had to be abandoned because of toxic smoke and fumes.

Investigators believe a worker dragging his foot along the floor while chemicals were being mixed sparked Thursday’s explosion. That worker is hospitalized with critical burns. Another worker was treated for lesser injuries.

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