Dippin' Dots human resources official Steve Heisner told WPSD initial reports of only two injuries immediately following the blast have been revised to confirm four injuries, but the extent of the injuries remains unknown.
Meanwhile, City of Paducah Spokeswoman Pam Spencer told the news station in a statement that in addition to the explosion, a nitrogen leak was detected inside the plant, but it was not immediately clear if the leak caused the explosion or was a result of it.
Liquid nitrogen is used to freeze Dippin' Dots ice cream.
Heisner also told WPSD the extent of the damage to the facility is not yet known and employees were not allowed to re-enter the plant because the power was shut off and oxygen levels were too low.
"We do not yet know what the cause of that explosion was," Heisner told KFVS, adding, "We will soon be able to get inside safely, and make an assessment of what has occurred. The building is all intact. There was an isolated explosion, for lack of a better term."
"We have very few employees that work the night shift. All employees have been accounted for," Heisner told the news station.