In this screen grab from video provided by WPVI-TV/6ABC, smoke rises from an explosion at the R.M. Palmer Co. plant in West Reading, Pa., Friday, March 24, 2023. (WPVI-TV/6ABC via AP)
CNN  — 

A fourth person has been confirmed dead in an explosion at an eastern Pennsylvania candy factory, officials said Sunday, as rescue crews continue to search for three others who remain missing amid waning hope of finding more survivors.

Rescue crews located the fourth victim in the early morning hours, West Reading Police Chief Wayne Holben said in a news conference, beneath the debris at the site of the explosion, which occurred Friday evening at the R.M. Palmer Co. facility.

“I want to assure you all that we will not rest until every single person affected by this tragedy has been accounted for,” Holben said. “We are fully committed to this task and we will do everything in our power to ensure that we bring closure to all those involved.”

He described the ongoing search and rescue effort as a “long process.” Crews have stopped using drones and heat imaging devices to locate survivors, he said, and are using heavy equipment to “methodically” remove debris, “taking as much care as possible for individuals that are still inside.”

Officials acknowledged they’re in a race against time. While first responders are working to reunite families with their missing loved ones, “the chance of finding survivors is decreasing rapidly,” Fire Chief Chad Moyer said Saturday, citing the “violence of the explosion and the amount of time that has passed.”

Officials continue to investigate the cause of the explosion, which leveled the factory building just before 5 p.m. Friday and dismayed West Reading, a community about 50 miles northwest of Philadelphia that’s home to about 4,500 people.

West Reading Mayor Samantha Kaag became emotional during Sunday’s news conference, saying her community was facing a “difficult time.”

“We really, truly do take this as seriously as we can and I am really, truly proud of every single person in this room right now, for being as strong and as confident and as graceful as they have in dealing with this and handling this,” the mayor said, resting her hand first on the shoulder of the police chief and then on her own heart. “We really truly do feel for everybody affected by this.”

Pennsylvania Gov. Josh Shapiro visited the site Saturday, pledging in a later statement “any and all Commonwealth resources needed to support ongoing recovery efforts.”

Local officials also heard from the White House, which offered condolences and told the mayor to reach out if the city needs anything, Kaag said.

R.M. Palmer – a manufacturer of seasonal chocolate novelties, like Easter chocolate bunnies – is “devastated by the tragic events,” it said in a statement.

“We have lost close friends and colleagues, and our thoughts and prayers are with the families and friends of all who have been impacted,” the company wrote on Facebook.

R.M. Palmer said it is “anxious” to be in touch with employees and their families, but the company’s email, phones, and other communication systems are down.

“Therefore we are relying currently on first responders and disaster recovery organizations to provide any available information to impacted families,” according to the statement. “We will be providing additional information and making contact with employees, impacted families, and the community as soon as possible.”

Residents asked to stay away from the scene

At a news conference Saturday, Holben corrected earlier information that had been released by the Pennsylvania Emergency Management Agency claiming five people had died. He also said one person had been rescued alive.

One woman who was found alive Saturday morning was conscious when she was discovered in the rubble of the lower floor of the building, the police chief said Sunday. There was no update on her condition.

A spokesperson for the Reading Hospital told CNN Saturday that at least eight individuals were hospitalized following the explosion. Of those, one patient had been transferred, two are in fair condition, and five have been discharged.

The hospital sent six ambulances – including their mass casualty incident vehicle – to the scene following the explosion.

While officials believe neighboring buildings are still structurally sound, Holben on Saturday said the scene was too dangerous for the public to get near as crews continued to look through debris.

That request was echoed by Kaag, who asked in a Facebook post for “continued cooperation from the public to avoid the area as emergency response workers continue to traverse the difficult task of recovery & assessing damage that will continue throughout the weekend.”

The mayor also announced a state of emergency in response to the explosion at a Saturday news conference.

“This morning at approximately 1 a.m., I issued a declaration of emergency to gather resources for the tragedy that happened with our home,” Kaag said. “This declaration is strictly to access more resources for emergency services and first responders on scene. Search and rescue efforts continue to push forward.”

“We are doing our best to control the flow of information and disseminate it as quickly as possible,” she added.

‘The house shook and the windows shook’

One local resident told CNN on Saturday that the deadly blast first sounded like an earthquake or someone driving into a nearby home.

Speaking to CNN’s Danny Freeman, Chris Suglia said he ran to his window to see what had caused the commotion Friday evening.

“It was a huge explosion around 5 o’clock, I’m about two blocks away from this location, it almost sounded like a vehicle of some sort ran into the house,” he said. “The house shook and the windows shook, and it was you know, pretty crazy.”

Suglia said after hearing the explosion, he went outside, where neighbors were also trying to figure out what happened. He said he was devastated to see the flames, which he described immediately following the explosion as “nonstop.” Suglia said he watched as firefighters battled to fight the blaze.

“We just all came together as a community and asked each other, ‘is everyone OK?’ you know, ‘is everyone alright?’”

R.M. Palmer has long been a major part of the local community, Suglia said. The candy company launched in 1948 and has been at its current location since 1959, according to the company’s website.

“It’s sad. It’s devastating. I mean nobody expects to go to work and not come home you know, especially for something like that,” Suglia said.

CNN has reached out to the Pennsylvania Emergency Management Agency for further details on the casualties.

CNN’s Andy Rose, Geoffrey Mills, Nicole Grether and Celina Tabor contributed to this report.