Authorities confirmed the death toll has risen to four after a catastrophic explosion occurred at a chocolate factory in West Reading, Pennsylvania.

At a news conference on Sunday morning, the police also reported that three individuals remain unaccounted for.

The explosion took place at the R.M. Palmer Company around 5 p.m. on Friday.

Eyewitnesses described hearing a massive blast from the candy factory, followed by the sight of flames.

Kristen Wisniewski, who resides three blocks away from the renowned local chocolate manufacturer, said, "It was the loudest thing I've ever heard in my life. The ground felt like it collapsed beneath us. The entire house shook, and my dogs were petrified, unable to move. It was terrifying."

The destruction is widespread, with the RM Palmer Building #2 being obliterated and neighboring Palmer Building #1 sustaining damage.

Mayor Samantha Kaag stated, "It's pretty leveled, and sadly, there isn't much left to salvage. The blast was so powerful that it shifted the front building with the church and apartments four feet forward."

There has been no confirmation regarding the cause of the explosion, including the possibility of a gas leak.

UGI Utilities spokesperson Joseph Swope said on Saturday that teams were dispatched after the explosion caused damage that led to the release of gas, fueling the ensuing four-alarm fire. He added, "We did not receive any calls about a gas leak or gas odor before the incident, but we are cooperating with the investigation, which will include checking all our facilities in the area."

Relatives and friends of factory employees are anxious but hopeful. Frankie Gonzalez spoke to Action News about his sister, who remains missing after the blast. "My sister went to work and never returned home. She's one of the few people still unaccounted for. We're hoping she found a safe spot to hide, and we're not giving up hope."

Gonzalez's sister has a daughter, son, and husband waiting for her at home. The family continues to pray as rescue efforts persist through the night.

Chief of Police Wayne Holben announced that one person was discovered alive and rescued from the debris overnight on Saturday. He added, "The discovery of life overnight gives us hope that others may still be found as rescue workers continue their search for any possible survivors."

A woman who worked on the second floor of the factory was discovered alive in the basement between 2 a.m. and 3 a.m. She was found after rescue workers shouted, "This is the fire department, is anyone there?" Having spent approximately eight hours under the debris, she was taken to the hospital, but her current condition and identity remain undisclosed.

Rescue operations are ongoing, employing specialized equipment and techniques, including dogs and imaging devices, to detect signs of life while cautiously removing rubble. The names of the deceased have not been revealed.

Tower Health reported on Saturday that Reading Hospital received a total of 10 patients. "One was transferred to Lehigh Valley Hospital, one to Penn State Health St. Joseph Medical Center, two have been admitted and are in good and fair condition, and the others have been discharged," stated the health system.

Garry Witmoyer from Wyomissing and his son, Garry Witmoyer Jr., were among the first to hear the explosion. Garry Sr. recalled, "I didn't know what to think. I just came running out and saw that mess over there. I think it was a gas explosion, the way it sounded." His son added, "I didn't see flames at first, just a bunch of shingles and materials falling from the sky. I knew it was an explosion."

Mayor Kaag explained that people were advised to move a block away in each direction, but no evacuations were ordered. She issued an emergency declaration to provide additional resources for first responders. Borough manager Dean Murray mentioned that some residents were displaced from the damaged apartment building.

Philip Wert, the West Reading council's vice president, said the building was constructed in the late 1950s or early 1960s, and officials had to "access our archive to pull the blueprints last night to get a better layout of the building and the mechanicals and utilities, and where things are."

He expressed optimism, saying, "The silver lining in all this is someone was found alive, someone was found alive that was in rubble, not knowing whether they were going to live or die, and fortunately, we found that person, and they've got a second chance, and hopefully, fingers crossed, we're going to find more."

R.M. Palmer Company released the following statement on the incident Saturday afternoon:

"Everyone at RM Palmer is devastated by the tragic events at one of our West Reading facilities and we are focused on supporting our employees and their families. We have lost close friends and colleagues, and our thoughts and prayers are with the families and friends of all who have been impacted. We are sincerely grateful for the extraordinary efforts of all of the first responders and for the support of our Reading community, which has been home to our business for more than 70 years. We will continue to coordinate closely with local and national agencies to assist in the recovery process.

We are anxious to be in touch with all employees and the families of employees who have been impacted, but the company's email, phones, and other communication systems are down, and therefore we are relying currently on first responders and disaster recovery organizations to provide any available information to impacted families. We will be providing additional information and making contact with employees, impacted families, and the community as soon as possible."

R.M. Palmer also released a crisis hotline on Saturday for families and anyone who needs support. The number is 610-374-5224 and the extension is 539.

The company's website says it has been making "chocolate novelties" since 1948 and now has 850 employees at its West Reading headquarters.

Governor Josh Shapiro and PEMA Director Randy Padfield visited the site on Saturday. Shapiro pledged ongoing resources and support.

"Our hearts break for the families of those who didn't come home," Shapiro said in a statement. "We are with you - and my Administration is here to provide all the resources and support West Reading needs."

Others in the community, such as volunteer groups in Berks County, have also pledged their support in helping those impacted by the explosion.

"I've never been more proud of Berks County, I've never been more proud of West Reading. We really did come together as a family and a community," noted Kaag.

The Associated Press contributed to this report.