Dozens of firefighters sifted through the wreckage left from the two-story brick building hours after rescuers pulled a young girl's body from the rubble and accounted for everyone else trapped inside.
Investigators were trying to determine whether ongoing construction at one of the ground-level stores, which sold wedding gowns, was to blame for the collapse about 50 miles northwest of Little Rock. Authorities had not declared an official cause by Monday evening.
"We don't know how or why they collapsed," said Brandon Baker, the director of emergency management in Conway County. "We just know it was fast."
Of the 10 people inside the building, Baker said one died and four others were injured. But a local hospital confirmed five people who were injured. Two were airlifted to area hospitals and three others who were treated at St. Vincent in Morrilton, CEO Christy Hockaday said. Two of the people treated at the local hospital were later released, Hockaday said.
Conway County Sheriff Mike Smith said a young girl died, but he declined to identify her because authorities were still trying to get in touch with her relatives.
Brian Matthews, who owns an auto detailing shop nearby, said he heard a loud crash about noon.
"When I looked up, there was nothing but smoke," he said.
Matthews rushed to the rubble, where he and a few other men spotted a woman pinned under a beam screaming, "My baby is still inside." They pulled bricks and wood off her, exposing her injured legs as she continued to cry out.
Meanwhile, some of the rescuers started searching for the missing child. But the little girl was lifeless by the time they found her under some bricks and part of a wall. Her body was hoisted from the rubble shortly after noon, Matthews said.
Rescue teams planned to dig through the debris overnight, in case someone was injured outside the building's perimeter, authorities said. Some workers inserted tiny cameras into crevices between crumbled bricks to make sure no one else was trapped.
Some people in the building had noticed creaking and groaning noises over the past few days, Mayor Stewart Nelson said.
The collapsed building closed off a stretch of downtown Morrilton, a working-class city of 6,700. Broken bricks and twisted metal slumped over the street corner where the building once stood. A broken clothes rack showed off a few colorful dresses, mostly untouched by the barrage of debris.
Down the street, Kylie Cole, 32, thought a train from the nearby depot collided with a car when she heard the building collapse. By the time she made it near the stores, all she could see was dust.
"We heard people screaming and crying," she said.
Associated Press writers Nomaan Merchant and Jeannie Nuss contributed to this report.