Officials in this small Texas town ravaged by a fertilizer company explosion started allowing residents to return to their wrecked homes to collect belongings on Saturday afternoon.

The owners of the West Fertilizer Co. plant, which triggered a massive explosion Wednesday night, issued a statement Friday expressing regret for the 14 deaths and massive structural damage caused by the blast.

Owner Donald Adair said his “heart is broken with grief for the tragic losses,” noting that one of his employees, who was a volunteer firefighter, was among the dead. The toll of the explosion, which damaged 50 homes and wounded roughly 200 people, “will continue to hurt deeply for generations to come,” Adair added.

The explosion has raised troubling questions about the oversight of plants that store highly volatile chemicals such as ammonium nitrate, which has been used to make bombs.

Initiatives to tighten regulations over such plants in the wake of the 1995 Oklahoma City bombing — which was carried out with a device made with ammonium nitrate — and the Sept. 11, 2001, attacks have been insufficient, critics say.

See photos and locatios of the damage

Fertilizer facilities that hold more than 400 pounds of ammonium nitrate are required to register with the Department of Homeland Security. The West company failed to do so, even though it submitted a state form last year noting it had 270 tons in stock.

Rep. Bennie Thompson (D-Miss.), the ranking member on the House Committee on Homeland Security, said in a statement that it seemed the company “was willfully off the grid.”

“DHS did not even know the plant existed until it blew up,” he said.

Officials in Texas say they intend to study what type of state and local legislation might be needed to address loopholes and beef up regulations for the hundreds of fertilizer plants around the state.

On Saturday afternoon, West officials said the Texas Fire Marshal’s Office and the Bureau of Alcohol, Tobacco and Firearms and Explosives had completed their investigations and determined that certain areas within the blast zone were safe enough to allow residents back to gather belongings. The cause of the fire that triggered the blast remains unclear, but officials have said nothing to suggest that they suspect foul play.

Earlier in the day, officials reported that small fires in the area had been set by leaking gas. The blazes appear to have been quickly contained.

Residents who had evacuated from the blast zone expressed frustration on Saturday, saying they are eager to assess the damage and collect prized belongings. Judy Goetz, a 67-year-old widow who was sitting on her porch when the blast thrust her against the wall of her house, said she’s losing patience.

“I want to go check on my jewelry and my guns,” she said, noting that her late husband has a collection of antique weapons. “I want to make sure that they are fine.”

She said she and other residents want to know how much local and state leaders knew about the risk the plant posed to the nearby schools and homes.

“It’s been there so long,” she said.