A boiler explosion at a cardboard box plant in St. Louis on Monday killed three people and injured four more, fire officials said.
The blast at Loy-Lange Box Company sent part of the boiler crashing into a nearby building housing a linen laundry service, according to local Fox News affiliate KTVI.
Two of the injured were listed in critical condition and transported for treatment by emergency medical services, the St. Louis Fire Department said on Twitter. Two others suffered non-life threatening injuries.
One of those killed was a box factory employee, and two of the dead worked at the linen service, the St. Louis Post-Dispatch reported, citing fire officials.
The Loy-Lange Box Company could not be immediately be reached for comment.
The company, founded in 1897, produces corrugated cardboard boxes as well as product displays, according to its website.