The flooding in southeast Texas has severely affected oil and chemical plants. Many have shut down operations in the past few days, including, the Colonial Pipeline, which carries huge amounts of gasoline and other fuel between Houston and the East Coast.
The largest refinery in the country, have also closed some facilities. Two explosions and plumes of black smoke were reported at a flooded chemical plant in Crosby, Texas on Thursday. Officials said they expected a chemical reaction that will likely cause a fire that will "resemble a large gasoline fire." A threat of additional explosion remains. Residents living within a 1.5-mile (2.4km) radius of the plant had been evacuated amid fears of such an event. One police officer who was helping secure the site was taken to hospital after inhaling fumes, while nine others admitted themselves as a precaution.
Parts of Texas have been hit by more than 50in of rainfall since Hurricane Harvey landed on 25 August. More than 32,000 people are being housed in emergency shelters. At least 37 deaths related to Hurricane Harvey and its aftermath have been reported in Texas. Firefighters are due to begin a door-to-door search of badly flooded areas of Houston on Thursday, to rescue survivors who are still stranded and recover the bodies of those who have died. Large parts of Houston, the fourth most populous city in the US, remain under water.