Blast at flood-hit Texas chemical plant

Two explosions have been reported at the flood-hit Arkema SA chemical plant in Crosby, Texas, and a sheriff's deputy was taken to a hospital after inhaling chemicals.

The company said it was notified by the Harris County Emergency Operations Centre of two explosions and black smoke coming from the plant in Crosby.

"Organic peroxides are extremely flammable and, as agreed with public officials, the best course of action is to let the fire burn itself out," the company said.

"We want local residents to be aware that product is stored in multiple locations on the site, and a threat of additional explosion remains. Please do not return to the area within the evacuation zone."

The Harris County Sheriff's Office said on its Twitter feed the deputy had been taken to the hospital and nine others drove themselves to the hospital as a precaution.

The company evacuated remaining workers at the damaged plant on Tuesday, and Harris County ordered the evacuation of residents within a 2.4km radius of the plant, which makes organic peroxides used in the production of plastic resins, polystyrene, paints and other products.

"Remain well clear of the area and follow directions of local officials," the National Weather Service said after the explosions, noting that winds were from the west to the east at 14km/h.

Richard Rowe, chief executive officer of Arkema's North America unit, told reporters on Wednesday that chemicals on the site would catch fire and explode if they were not properly cooled.

The company said it opted not to move chemicals before the storm but made extensive preparations. The plant is 40km northeast of Houston.