FAIRVIEW TOWNSHIP (KDKA/AP) – Investigators are working to determine what caused an explosion and fire on the grounds of a chemical plant in northern Butler County Thursday afternoon.

People who live nearby say the explosion was so massive they felt their houses shake more than three miles away from the scene.

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“I was inside sitting on the couch, and all of the sudden, the windows, the roof… I thought my roof blew off,” said Robin McGinnis, who lives across the street from the plant. “I thought it was storming out at first. Then, when I came outside there was pressure and it scared the daylights out of everybody in the neighborhood.”

According to emergency dispatchers, the fire began around 1:30 p.m. at the Sonneborn Chemical Plant in Fairview Township. The plant is located in the 100-block of Sonneborn Lane.

KDKA’s Brenda Waters reports from the scene that no one was injured. Also, earlier, there were reports some nearby residents may have needed to be evacuated, but that turned out not to be the case.

The Sonneborn Chemical Plant has operated in the Borough of Petrolia for more than 120 years. The plant makes waxes and other products including petrolatum, which is used in baby oil and petroleum jellies.

Just over 200 people live in the community and many of them work at the plant.

“We just felt a large boom,” said Anita Orozco, a plant representative. “I’m not sure what it was. At first, it felt like an overactive electrical strike. We walked outside and saw that it was an issue up on what we call ‘the hill,’ which is where our hydrogen plant is. That’s where we process all of our raw feed stocks to be able to turn it into the products that we make.”

Most of the fire crews were being released from the scene by 3 p.m.

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Terri Saylor lives more than three miles from the plant. She felt the explosion and was concerned about a family member.

“I felt the house shake and I thought it was thunder, like really bad thunder,” she said. “I spoke to my daughter, which she works over there and she said that it shook her. She had to hold onto a filing cabinet to stay on her feet.”

The evacuations were not necessary because, according to the company, nothing produced at the plant is a threat to humans or the environment.

Paramedics did check out two of the workers at the scene, but both refused treatment.

There was another fire at the plant two years ago. No one was injured in that fire either.

Officials at the Sonneborn Corp. plant declined immediate comment.

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