Officials have recovered 14 bodies following a massive explosion that levelled a fertiliser plant and destroyed dozens of homes in West, Texas.
Texas Department of Public Safety Sgt Jason Reyes did not say where the bodies were found but said more information would be provided later.
He says the bodies will be sent to the Dallas County medical examiner's office for identification.
The blast levelled nearby apartments Sgt Reyes earlier announced that 12 bodies had been recovered by Friday morning and that search and rescue efforts were ongoing.
Senator John Cornyn, speaking earlier to reporters in West, said as many as 60 people remain unaccounted for, but suggested some could be staying with friends and relatives.
Even before investigators released a confirmed number of fatalities, the names of the dead were becoming known in the town of 2,800.
A small group of firefighters and others who may have rushed toward the factory to battle a pre-explosion blaze are believed to be among the dead. Sgt Reyes said he could not confirm how many of those killed were first responders.
Mourners gather for a candle light vigil at a church in West Authorities said there is no indication that the blast was anything other than an industrial accident. It remains unclear what sparked the blaze.
"We know everyone that was there first, in the beginning," said Christina Rodarte, who has lived in West for 27 years. "There's no words for it.
"It is a small community, and everyone knows the first responders, because anytime there's anything going on, the fire department is right there - all volunteer."
One victim Ms Rodarte knew and whose name has been released was Kenny Harris, a 52-year-old captain in the Dallas Fire Department who lived south of West. He was off duty at the time but responded to the fire to help, according to a statement from the city of Dallas.
A massive plume of smoke filled the Texas sky after the blast West's landscape is likely to be altered permanently after an area four to five blocks in radius was levelled by the blast. An apartment complex was badly shattered, a school set ablaze, and a nursing home was left in ruins.
Residents have been kept out of a large swathe of West, where search and rescue teams continue to pick through the rubble.
Some with permission have made forays closer to the destruction and came back stunned - and it is possible other residents will be allowed to retrieve some personal belongings on Friday, emergency workers said.
Texas attorney general Greg Abbott said: "I had an expectation of what I would see, but what I saw went beyond my expectations in a bad way. It is very disturbing to see the site."
Firefighter Darryl Hall, from Thorndale, about 50 miles away from West, was one of the rescue workers helping with the house-to-house search.
He said: "People's lives are devastated here. It's hard to imagine."
A nearby football pitch served as a makeshift triage in the aftermath A team from the Bureau of Alcohol, Tobacco, Firearms and Explosives still had not been able to begin investigating the scene because it remained unsafe, agency spokeswoman Franceska Perot said.
The West Fertilizer Co facility stores and distributes anhydrous ammonia, a fertiliser that can be directly injected into soil, and a blender and mixer of other fertilisers.
Records reviewed by the AP news agency show the US Pipeline and Hazardous Materials Safety Administration fined West Fertilizer $10,000 last summer for safety violations that included planning to transport anhydrous ammonia without a security plan.
An inspector also found the plant's ammonia tanks were not properly labelled.
In a risk-management plan filed with the Environmental Protection Agency about a year earlier, the company said it was not handling flammable materials and did not have sprinklers, water-deluge systems, blast walls, fire walls or other safety mechanisms in place at the plant.
State officials require all facilities that handle anhydrous ammonia to have sprinklers and other safety measures because it is a flammable substance, according to Mike Wilson, head of air permitting for the Texas Commission on Environmental Quality.
But inspectors would not necessarily check for such mechanisms, and it is not known whether they did when the West plant was last inspected in 2006, said Ramiro Garcia, head of enforcement and compliance.
That inspection followed a complaint about a strong ammonia smell, which the company resolved by obtaining a new permit, said the commission's executive director Zak Covar.
He said no other complaints had been filed with the state since then, so there have not been additional inspections.
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