Sandra Jimenez, left, and her sister Karla Jimenez look at the ruins of an apartment complex, reflected in the window, in Silver Spring, Md., on Friday. Their brother Augusto Jimenez and his wife, Maria Castellon, are still missing. (Michael Robinson Chavez/The Washington Post)

Most evenings, Maria Castellon prepared a traditional dinner that often featured the Nicaraguan style of mixed rice and beans known as gallo pinto. She usually headed to bed by 10 p.m., while her husband, Augusto Jimenez, stayed up a little longer, listening to music or watching sports.

Now, the son who shares his father’s name, Augusto Jimenez, 35, said he fears his parents did not make it out of their Silver Spring apartment when an explosion and fire ripped through the building late Wednesday.

“Each hour that goes by, we are less hopeful we will find them alive,” Jimenez said Friday, speaking in Spanish.

Jimenez is among those who have been enduring an anguished wait, unable to find family members or other loved ones who lived in the Flower Branch Apartments.

Authorities in Montgomery County, Md., have recovered the bodies of three people who died in the blast and fire that nearly leveled a building. They said Friday that they thought “a number of people” were still in the rubble but did not specify how many people were missing.

Augusto Jimenez and Maria Castellon are shown in this family photo.The husband and wife are among the tenants missing after a fatal explosion and fire Wednesday in Silver Spring.

The three people known to have died have not yet been identified, police said, and the cause of the tragedy is still not known.

Officials on Friday said recovery efforts were complicated by oppressive heat and humidity and by the structural instability of the burned apartment building, which they said required them to work slowly and methodically to keep personnel safe.

Rosi Lopez, a resident of the building, told Univision Washington that the blast woke her but that she could not reach her 9-year-old son as their apartment collapsed. She said she was knocked unconscious and was pulled to safety by neighbors.

“I am left with nothing,” Lopez told the station in Spanish. “I lost everything. I lost my child.”

Angie Paniagua, 28, said Friday that since the fire, she has not been able to reach her father, who lived in the building.

A retired painter, Saul Paniagua, 65, migrated from Guatemala nearly three decades ago. His life was focused on his family, especially two granddaughters whom he spoiled with ice cream and other sweets.

As Angie Paniagua held out hope that her father is alive, perhaps hospitalized, she spoke of him in the past tense.

“He was the best husband. He was the best father and the best grandfather,” she said.

Her mother, who has been ill and living in a nursing home, was not yet aware of what had happened, she said. And she is not sure how she will tell her two daughters, who are 12 and 7.

Augusto Jimenez said that when he heard about the explosion, he tried unsuccessfully to reach his parents by phone. He and other relatives have searched the shelter where displaced families were relocated and have visited hospitals. They asked neighbors about the couple, but no one had seen them.

“We are hoping for a miracle,” Jimenez said. “But if they made it out, they would have called us by now.”

Jimenez’s parents, Augusto Jimenez and Maria Castellon, lived at the Flower Branch complex for 16 years and had worked together for years cleaning homes in the Washington area.

The couple left their native Nicaragua in the early 1990s to come to the United States in search of economic opportunity. They settled in Silver Spring, Md., and their children joined them a few years later.

The elder Jimenez spent his free time playing the piano in the couple’s two-bedroom apartment. In Nicaragua, he was in a band that played various genres of music, but when he settled in the United States, he became passionate about new-age melodies that he said soothed the soul. He would record his music and give it away to friends and family members.

“He had a mini music studio in the living room of the apartment where he recorded his music. When someone was celebrating a birthday or a special occasion, he would make them a special CD with his music,” the son said.

Jimenez described his mother as quiet and devoted to her grown children. She would cook for them anything they requested, he said.

“She was friendly and kind to everybody,” he said, “and that’s why everybody loved her.”

The couple have two children in the Washington area and two in Nicaragua. They were looking forward to meeting their youngest grandchild, a 4-month-old girl who lives in Nicaragua.

“They still had so many plans,” their son said. “I know that we are all destined to die, but not in these circumstances.”

Antonio Olivo, Emma Brown and Eddy Palanzo contributed to this report.