NORTH ANDOVER, Mass. - An explosion at Dow Chemical plant in northeastern Massachusetts injured four people and damaged part of the building Thursday afternoon.
Firefighters, paramedics and police responded to the plant in North Andover at about 2:30 p.m.
Several people were injured and rushed to the hospital.
The State Fire Marshal Stephen Coan said a chemical reacted with water in a lab in Dow Chemical, which caused the explosion.
What caused Thursday's reaction and explosion is unclear. Fire officials in North Andover say the town works closely with Dow and after an event like this is ready to help.
FOX25 spoke to some people who heard the explosion and they say it sounded like a train was going over their building.
Emma Jurkiewicz was playing tennis at the time and said the "sound was kind of like a mini bomb in a way."
Now, everyone is just hoping all of the victims pull through.
"I feel very sorry for them and I hope they pull through," one person said.
One victim remains in critical condition at Lawrence General Hospital while three others were taken to Boston area hospitals and are also listed in critical condition.
Investigators are expected to return to the plant on Friday to do more testing to confirm what caused this explosion.
© 2017 Cox Media Group.