CNN  — 

At least six people died at an Amazon (AMZN) warehouse building collapse after an EF-3 tornado caused major structural damage to the building Friday, according to the Edwardsville Fire Department in Illinois.

Forty-five people made it out of the building, with one person airlifted to a regional hospital for treatment, Edwardsville Fire Chief James Whiteford said during a Saturday evening news conference.

Amazon workers identified as dead by the local coroner were Deandre S. Morrow, 28, of St. Louis, Missouri; Kevin D. Dickey, 62, of Carlyle, Illinois; Clayton Lynn Cope, 29, of Alton, Illinois; Etheria S. Hebb, 24, of St. Louis, Missouri; and Larry E. Virden, 46, of Collinsville, Illinois. Amazon cargo driver Austin J. McEwen, 26, died trying to shelter from a powerful tornado in the bathroom at the warehouse, according to a coworker.

“He was my friend and he didn’t make it,” said coworker Brian Erdmann, who was on his way to make a delivery to the warehouse. “If I would have got back 45 minutes earlier, I probably would have been at the same place. I would have been right there with him.”

The recovery phase is expected to take three more days and first responders will continue “to search the site for evidence of life,” Whiteford said.

“Earlier this afternoon, the response portion of this incident came to a close and we’re now focused solely on recovery,” Whiteford said.

Amazon Worldwide Consumer CEO Dave Clark said the company’s staff was saddened at the loss of life at the facility and beyond.

“Our thoughts and prayers are with the victims, their loved ones, and everyone who has been impacted by the storm’s path across the U.S. We’re continuing to provide support to our employees and partners in the area and across the communities affected by the storms. We also want to thank all of the first responders for their ongoing efforts on the scene,” Clark said in a tweet.

Several employees told Reuters that they had been directed to shelter in bathrooms by Amazon managers after receiving emergency alerts on mobile phones from local authorities. The first warning was issued about 40 minutes before the tornado hit, according to firefighters and the Illinois governor.

Amazon confirmed in an email that the site got tornado warnings through various alerts. “Our team worked quickly to ensure as many employees and partners could get to the designated Shelter in Place,” the company said in a statement. “We thank them for everything they were able to do.”

Workers gave conflicting accounts as to whether the bathroom was the designated shelter. Amazon did not comment.

Some of those workers said they had kept their phones in violation of an Amazon policy that prevents them from having cellphones at work.

The company responded by saying employees and drivers are allowed to have their cellphones.

“I was at the end of my route. I was just getting in the building and they started screaming, ‘Shelter in place!’” said David Kosiak, 26, who has worked at the facility for three months. “We were in the bathrooms. That’s where they sent us.”

“It sounded like a train came through the building. The ceiling tiles came flying down. It very loud. They made us shelter in place til we left - it was at least two and a half hours in there.”

Retail, Wholesale and Department Store Union criticized Amazon for requiring employees to work through a tornado warning.

“This is another outrageous example of the company putting profits over the health and safety of their workers, and we cannot stand for this. Amazon cannot continue to be let off the hook for putting hard working people’s lives at risk. Our union will not back down until Amazon is held accountable for these and so many more dangerous labor practices,” said Stuart Appelbaum, President of the RWDSU.

The chief said approximately 150 yards of the building collapsed after the tornado touched down at 8:35 p.m. CT on Friday.

Edwardsville is approximately 25 miles northeast of St. Louis, Missouri.

CNN’s Ramishah Maruf contributed to this report.

CNN’s Ramishah Maruf contributed to this report.