WEST, — Rescuers searched the smoking remnants of a Texas farm town Thursday for survivors of a thunderous fertilizer-plant explosion, gingerly checking smashed houses and apartments for anyone still trapped in debris or bodies of the dead.

Initial reports put the number of fatalities as high as 15, but later in the day, authorities backed away from any estimate and refused to elaborate. More than 160 people were hurt.

A breathtaking band of destruction extended for blocks around the West Fertilizer Co. in the small community of West. The blast shook the ground with the strength of a small earthquake and leveled dozens of homes, an apartment complex, a school and a nursing home. Its dull boom could be heard dozens of miles away from the town about 20 miles north of Waco.

Waco police Sgt. William Swanton described ongoing search-and-rescue efforts as “tedious and time-consuming,” noting that crews had to shore up much of the wreckage before going in.

Industrial accident

Searchers “have not gotten to the point of no return where they don’t think that there’s anybody still alive,” Swanton said. He did not know how many people had been rescued.

There was no indication that the blast, which sent up a mushroom-shaped plume of smoke and left behind a crater, was anything other than an industrial accident, he said.

The Wednesday night explosion rained burning embers and debris down on terrified residents. The landscape was wrapped in acrid smoke and strewn with the shattered remains of buildings, furniture and personal belongings.

Dogs with collars but no owners trotted nervously through deserted streets in cordoned-off neighborhoods around the decimated plant. The entire second floor of a nearby apartment complex was destroyed, leaving bricks and mattresses among the rubble.

One rescue crew going from apartment to apartment gave special attention to a room where only a child’s red and blue bunk bed remained.

While the community tended to its deep wounds, investigators awaited clearance to enter the blast zone for clues to what set off the plant’s huge stockpile of volatile chemicals.

“It’s still too hot to get in there,” said Franceska Perot, a spokeswoman for the Bureau of Alcohol, Tobacco and Firearms.

Uncertain death toll

The precise death toll was uncertain. Three to five volunteer firefighters were initially believed to be among the dead, which authorities said could number as many as 15. By late Thursday afternoon the state Department of Public Safety would not confirm how many had been killed.

Swanton said he would “never second-guess” firefighters’ decision to enter the plant, because “we risk our lives every day.” The many injuries included broken bones, cuts and bruises, respiratory problems and minor burns. Five people were reported in intensive care. Five more were listed in critical condition.

In the hours after the blast, residents wandered the dark, windy streets searching for shelter. Among them was Julie Zahirniako, who said she and her son, Anthony, had been at a school playground near the plant when the explosion hit.

The explosion threw her son four feet into the air, breaking his ribs. She said she saw people running from the nursing home, and the roof of the school rose into the sky.

“The fire was so high,” she said. “It was just as loud as it could be. The ground and everything was shaking.”

First-responders evacuated 133 patients from the nursing home, some in wheelchairs. Many were dazed and did not know what happened.

William Burch and his wife, a retired Air Force nurse, entered the damaged nursing home before first-responders arrived. They searched separate wings and found residents in wheelchairs trapped in their rooms. The halls were dark, and the ceilings had collapsed. Water filled the hallways. Electrical wires hung eerily from the ceilings.

“They had Sheetrock that was on top of them. You had to remove that,” Burch said. It was “completely chaotic.”

Gov. Rick Perry called the explosion “a truly nightmare scenario for the community” and said he had been in touch with President Barack Obama, who promised his administration’s assistance with operations on the ground.

Authorities said the plant made materials similar to those used in the 1995 Oklahoma City bombing.