The explosion may be the worst since a blast at BP's Texas City refinery in 2005, which killed 15 workers and injured more than 100.
The United States' worst industrial accident also occurred in Texas, in April 1947, when a fire on board the SS Grandcamp freighter in the port of Texas City detonated a cargo of ammonium nitrate. The resulting explosions and fires killed more than 570 people.
Wilson, who likened the scene at West to the Iraq war, said the 50-home apartment complex now resembled a "skeleton," while a middle school and the West Rest Haven Nursing Home had both been badly damaged. Emergency responders evacuated 133 residents, including some in wheelchairs, from the nursing home.
Elizabeth Marquez-Perea, who lives in West about a mile north of the plant, said about 50 families lived at Tucker Apartments, the damaged block close to the facility. She and her three daughters fled after the blast shattered windows of their apartment. "It smelled like gas, a real terrible smell," she said.
About a month ago, the school close to the plant had sent parents a note explaining that children had been moved for the day to a different location because of smells coming from the fertilizer plant, Marquez-Perea said.
Vicky Pustejovsky, who works in customer service for Blue Cross Blue Shield and lives two blocks from the facility, said the town was in "complete disarray."
"We were watching TV when we heard the explosion," Pustejovsky said. "Our doors started caving in."
Residents were told by authorities to remain indoors because of the threat of new explosions or an ammonia leak from the plant.
Jonathan Moore, a 30-year-old truck driver, felt the blast from about 35 miles to 45 miles north in the town of Itasca. He said he heard a loud boom and saw the walls shake inside the truck-stop he was in at the time.