GATESVILLE, Texas (AP) - A worker severely burned in a 2018 deadly explosion at a Central Texas hospital has sued a Dallas-based utility seeking more than $1 million.

Matt Aaron of Oglesby alleges Atmos (AT'-muhs) Energy Corporation failed to maintain its natural gas system and include a "rotten egg" odor to alert of possible leaks.

Three people were killed and 13 hurt in the June 26 accident during construction at Coryell Memorial Hospital in Gatesville, 90 miles (144.83 kilometers) north of Austin.

Investigators in November concluded natural gas flowed from disconnected lines into a boiler room. Wednesday's lawsuit says Aaron, employed by Lochridge Priest Inc., was nearby. Officials aren't sure what ignited the gas.

Atmos on Thursday repeated earlier findings that no leaks were found in its natural gas system and odorant levels complied with regulations.

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