A chemical plant near the flooded city of Houston is expected to explode or catch in the coming days.
In heavy rainfall from Hurricane Harvey, the Arkema factory in Crosby lost the cooling of chemicals that need to be kept fresh, and there is no way to prevent a possible fire, the company said.
At least 33 people died after the storm.
The US energy supply is also affected, as the oil companies have closed pipelines.
The US National Weather Service lowered the hurricane from a tropical depression, but has predicted that heavy rain will continue over East Texas and West Louisiana.
What happened at the chemical plant?
The Arkema chemical plant closed its production on Friday before the stormhit the mainland.
But 40 centimeters of rain in the area flooded the site and cut their power, the company said in a statement. The backup generators were also flooded.
The plant produces organic peroxides and chemicals that are stored on site, can be dangerous at high temperatures.
“Some fire probably looks like a big gas fire,” said General Manager Richard Rowe Reuters news agency. “The fire becomes explosive and intense.”
He said the black smoke would irritate the skin, eyes, and lungs.
“The high water that exists on the site, and the lack of power, do not leave us any way to prevent it.”
“Everything is gone”
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Why was Houston not evacuated?
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The fire is expected to be mainly contained on the site itself, but the residents of Harris County were evacuated within a radius of 1.5 miles around the plant as a precaution.
The remaining remaining workers on the site were evacuated on Tuesday.
How are rescue operations continued?
Parts of Texas were hit by more than 50 inches of rain since Hurricane Harvey landed and set new records before it was degraded to a tropical storm and late Wednesday to a tropical depression.
Rescue efforts were continued overnight. Thousands of people were rescued from flooding across the country, and more than 32,000 people are still in emergency accommodations.