The cause of the explosion was a fire. The effect was devastation, and heartbreaking loss.

The destruction was so complete that the first confirmation of the number of people killed in the fertilizer plant explosion in West didn’t come until Friday morning, some 36 hours after the blast leveled parts of the small town 20 miles north of Waco. Twelve people were dead, authorities said. The number was later raised to 14, and the sad hint of additional loss hung in Friday’s announcement.

The trauma inflicted on the families who lost loved ones and on families who lost their homes will be long and deeply felt. We express our sorrow, even as we express pride for the West’s volunteer firefighters who rushed to put out the fire at the plant, and who tried to evacuate residents as danger grew imminent. We also thank the emergency and rescue crews from across the region who sped to West to help after the explosion.

West’s 2,800 residents — about 200 of whom were injured by the explosion — knew who hadn’t been seen since Wednesday evening. Small towns are tightly knit and West quickly began mourning the friends and neighbors who had been killed.

Aerial and other photographs revealed the deadly effect of an explosion that registered as a 2.1-magnitude earthquake. The blast destroyed or seriously damaged an apartment complex that was located across the street from the plant, a nearby middle school, a nursing home and scores of houses.

With the destruction came displacement and the need for help. The immediate and generous outpouring of support was not the least bit surprising. Central Texans have shown time and time again that we see no strangers when disaster strikes. Without being asked, donations began arriving to support the residents of West. The willingness of people to help those affected by the explosion is always heartening.

The fire that sparked the explosion appears, as of this editorial’s deadline, to be accidental. An FBI spokesman told The New York Times there were no signs of criminal activity in the explosion.

Tragic accidents carry lessons, and towns and the state must learn from the explosion in West. The West Fertilizer Co. had been in business since 1962, storing, blending and selling chemicals and fertilizer to farmers. The company handled two common fertilizers, anhydrous ammonia and ammonium nitrate.

Both fertilizers are potentially explosive if mishandled or not properly protected. Ammonium nitrate was used in the 1995 Oklahoma City bombing that killed 168 people. And almost 600 people were killed in Texas City in 1947 when ammonium nitrate exploded aboard a docked freighter.

Records reviewed by the American-Statesman, The Associated Press and other news outlets show that the federal government had fined West Fertilizer at least three times since 1985 for various safety violations. Subsequent reports show that the violations appear to have been corrected, though one recent record indicated the company had told the Environmental Protection Agency it did not handle flammable materials even though anhydrous ammonia is a flammable substance. In addition, state records show the plant did not have sprinklers or fire walls.

Given that the plant was 50 years old, it presumably was exempt from many regulations that have passed since its construction, and its owners can’t be held responsible for the houses and buildings that have popped up around the plant over the past few decades.

Zoning is not intrinsic to small, rural towns. They don’t face the same development pressures cities experience. But there are hundreds of fertilizer businesses similar to West Fertilizer in the state, and undoubtedly houses and schools have been built around some of them. Neither plants nor buildings can move, but closer inspections of the plants can take place, and tighter rules imposed.

Questions of zoning and safety have been raised since Wednesday’s explosion and will be part of the debate as governments and towns assess the need for new rules and regulations. But that debate can wait. First we mourn our Texas neighbors.