A federal investigation into what caused Monday’s deadly boiler explosion near Soulard could take months to complete. That’s according to a spokesman for the Occupational Safety and Health Administration.

Scott Allen said the investigation is particularly complicated due to the fact multiple people were killed or injured and because of the scope of the damage. Three people died in the accident. Four others were injured, two critically. Three buildings were also damaged in the blast.

Allen told 5 On Your Side OSHA compliance officers were on site Tuesday talking with employees at the Loy Lange Box company trying to determine whether any regulations were being violated. The facility is the site where the explosion happened.

St. Louis Fire Department officials say a van-sized high-pressure water tank associated with the boiler system is what launched into the air, crashed through the roof of the Loy Lange building and eventually landed on the Faultless Healthcare Linens building.

By law, OSHA investigators have six months to complete their work. Allen said the Loy Lange investigation could take much of that time.

On Monday, 5 On Your Side Investigates uncovered a number of OSHA violations reported in previous years at Loy Lange. You can find links to all those violations at the bottom of this story. Allen said investigators will take those violations into consideration, but said the boiler explosion investigation stands on its own.

5 On Your Side is working to learn more about the two unidentified victims who were killed in this accident. On Monday St. Louis Police announced 59-year-old Kenneth Trentham of St. Louis was killed inside the Loy Lange building. Trentham was working as a licensed stationary engineer at the time of the accident.

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Another inspection opened on the same day

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