At least 200 people were injured and 150 homes, three rescue trucks and a fire truck were destroyed in Wednesday's fire and explosion at the West Fertilizer Co. plant, USA Today reported.
Texas Department of Public Safety Sgt. Jason Reyes confirmed two more fatalities, bringing the official death toll to 14, the Waco Tribune-Herald reported.
Gov. Rick Perry visited the disaster scene and met with local officials.
"I'd like to thank everyone who has put so much time and determination into caring for their fellow Texans over the past two days," Perry said. "Whether they worked triage the night of the explosion, pulled extra shifts at area hospitals, or just took one of their displaced neighbors into their home they are the heart and soul of the Texas tradition of neighbor helping neighbor.
"No doubt, there is a lot of work that lies ahead and the road to recovery is long. But this community will come together, this community will mourn and this community will rebuild."
Donald Adair, the owner of Adair Grain Inc., which owns West Fertilizer Co., issued a statement saying it had been "a terrible week for everyone" in the town and expressing his "heartfelt sympathy for those affected and my appreciation for those who responded."
"As a lifelong resident, my heart is broken with grief for the tragic losses to so many families in our community," Adair said. "I know that everyone has been deeply affected by this incident. Loved ones have been injured or killed. Homes have been damaged or destroyed. Our hearts go out to everyone who has suffered.
"The selfless sacrifice of first responders who died trying to protect all of us is something I will never get over. I was devastated to learn that we lost one of our employees in the explosion. He bravely responded to the fire at the facility as a volunteer firefighter. I will never forget his bravery and his sacrifice, or that of his colleagues who rushed to the trouble.
"This tragedy will continue to hurt deeply for generations to come."
Adair said he and the company's employees would work with investigators.
Federal and state investigators were waiting Friday for clearance to enter the blast area to search for clues to the cause of the blast.
"It's still too hot to get in there," said Franceska Perot, spokeswoman for the U.S. Justice Department's Bureau of Alcohol, Tobacco, Firearms and Explosives.
West Volunteer Fire Department members and emergency medical service workers, the first on the scene of the fire, were among those killed, West Mayor Tommy Muska said.
Dallas fire Capt. Kenny Harris, who lived in West, was among those killed in the explosion, WFAA-TV, Dallas, reported.
"Capt. Harris rushed to the scene compelled to provide assistance to his community during this crisis," Dallas Mayor Mike Rawlings said. "I want to express my deepest condolences to his family, friends and co-workers."
Many homes and other buildings were flattened by the explosion Wednesday in the town of 2,500 residents. Search-and-rescue crews moved carefully from one shaky structure to another near the site of the explosion, shoring them up before searching for survivors.
Condolences came from around the world, including from Pope Francis, along with help from across the state. President Barack Obama called to offer federal support to Perry, who declared McLennan County a disaster area to begin the process of receiving federal aid for cleanup and reconstruction.
Texas Lt. Gov. David Dewhurst told CNN the cause of the disaster may not be determined for weeks.
"Unless we know something else, right now it's an industrial accident," he said. "But we're going to get to the bottom of this to find out what happened because we don't want to see this ever happen again."
Inspectors from the Texas Commission on Environmental Quality and the federal Environmental Protection Agency were in West to determine whether it was safe for rescuers to go onto the site.
Reyes said it was unclear when the affected area would be opened to residents, The Dallas Morning News said.
"It's still a very volatile situation," McLennan County Chief Sheriff's Deputy Matt Cawthon said.
Questions have been raised about safety at the plant. The company told the Texas Commission on Environmental Quality when it applied for a permit there was no risk of explosion from its two 12,000-gallon tanks of anhydrous ammonia, the Morning News said. The company, which distributes fertilizer to farmers, received the permit in December 2006.
However, the facility told a state agency in February it was storing as much as 270 tons of ammonium nitrate, the explosive chemical compound used in the April 19, 1995, attack on the Oklahoma City federal building, NBC News reported. The company's risk management plan filed with the federal EPA in 2011 did not mention ammonium nitrate.
NBC said the company has received several disciplinary actions from state and federal regulators since 2006.