The police in Edwardsville, Ill., said there were at least two “confirmed fatalities” at an Amazon warehouse after a direct hit from a tornado caused a major portion of the building to collapse on Friday night, leaving “catastrophic damage to a significant portion” of the building.

Three people were rescued from the building, and one of them was taken to a hospital, said Mark Mayfield, a captain with the Edwardsville Fire Department. He did not know the person’s status on Saturday morning but said he believed the person to be in “stable condition.”

Thirty workers made it out of the building safely by themselves, the police said. A bus carried several workers to reunite with families in nearby Pontoon Beach, said Michael Fillback, the Edwardsville police chief.

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Captain Mayfield said he did not know how many workers were inside the building when the tornado struck around 8:30 p.m., but Chief Fillback told the St. Louis station KDSK-TV on Saturday that the number was not “in the hundreds.” Chief Fillback estimated at a news conference on Saturday morning that about 50 people had been in the building.

Emergency responders received the initial call at 8:38 p.m. and arrived several minutes later, Captain Mayfield said, with about 100 responders on the scene shortly after the building collapsed. More than a dozen area police, fire and emergency medical service departments responded.

On Saturday morning, police blocked off the entrance to the campus, which is about 20 minutes northeast of St. Louis.

The building, which is two years old, is in a distribution hub on the west side of town with about 20 warehouses ranging from about 100,000 to 1.4 million square feet, he said. There is another Amazon warehouse across the highway. The tornado caused the collapse of a wall the size of a football field at the warehouse, along with the roof above it, according to The Associated Press.

“About half of it’s missing, it’s gone,” Captain Mayfield said of the building, which is about 400,000 square feet. The other half of the building remained standing on Saturday morning, he said, adding that workers were able to safely evacuate from that area.

“There’s a lot of debris from the concrete; that is predominately a concrete and steel structure,” Chief Fillback said on Saturday morning, adding, “It’s windy outside, so things are unstable.”

On Saturday morning, a steady stream of construction vehicles entered the scene. Workers appeared to be using a crane to clear wreckage from the site. Winds continued to blow at more than 20 mph Saturday morning, causing cars to shake.

Ingrid Barahona, 37, was on a delivery route 20 minutes away from the warehouse when the building collapsed.

On Saturday morning, she was trying to learn what happened to another worker who was still missing.

“I’m asking God that she was OK,” she said.

On Saturday morning, Ms. Barahona borrowed her sister’s car to drive with her 4-year-old daughter to a parking lot near the warehouse. Tow truck drivers were removing cars from the disaster site. Many of them were destroyed; Ms. Barahona’s car suffered significant damage.

Parked on the side of the road near the warehouse were Jordon and Kelsi Bryn of nearby Bethalto, Ill. They said they were relieved that Ms. Bryn’s mother, who works as a delivery driver at the Amazon facility across the highway from the damaged warehouse, was okay. They said the storm hit minutes after she got off work on Friday night.

Ms. Byrn’s mother told her that she had gotten out of the building just before Amazon told workers to shelter in place. “When she was on the highway, there were so many semis tipped over she had to pull a U-turn and wait under a viaduct until the storm passed,” Ms. Byrn said.

Captain Mayfield said that the remaining part of the building would probably have to be demolished. “I don’t see any way that they can salvage it,” he said.

Heavy machinery was brought in to move the collapsed walls to ensure that there were no other people unaccounted for, and rescue teams were checking inside vehicles that had been crushed by the collapsed walls.

“We’re deeply saddened by the news that members of our Amazon family passed away as a result of the storm in Edwardsville, Ill.,” Kelly Nantel, an Amazon spokeswoman, said in a statement on Saturday. “Our thoughts and prayers are with the victims, their loved ones and everyone impacted by the tornado.”

Amazon opened two warehouses in Edwardsville, about 25 miles east of St. Louis, in 2016, employing about 2,200 people, The St. Louis Post-Dispatch reported in 2017.