Two workers were injured at a public fireworks display in Valley Falls Thursday night, leaving two people with burns and a woman with a piece of heavy plastic embedded in her arm.

The workers were associated with the company putting on the annual fireworks show at the southern edge of Valley Falls. They suffered burns when fireworks accidentally detonated shortly after 10 p.m., said Jefferson County Sheriff Jeff Herrig.

Herrig said officials believe fireworks stored in an uncovered tote accidentally detonated, touching off a large volume of fireworks stored in two other containers. One male worker from Valley Falls suffered severe burns to his arm and was taken to a hospital in Topeka. The other worker, a woman from Ozawkie, also suffered burns and was first thought to have a broken arm, Herrig said. Later, it was determined that a piece of PVC plastic piping embedded in the woman’s arm from the accident had been mistaken for a protruding bone.

Neither of the workers’ injuries appeared to be life threatening, Herrig said. Both were transported by ambulance to a regional hospital, and the woman was later transferred to Kansas University Hospital. At least three other people declined medical treatment for minor injuries.

Herrig said the fire was still under investigation and it was unclear exactly how the fireworks had been accidentally ignited.