Pipeline Safety Trust

It is possible that after the gas line was hit that the gas migrated underground and into the apartment building, where it then reached explosive levels before igniting. It is also possible that the gas was ignited above ground as well. It's hard to pinpoint exactly what happened as we are still waiting for the investigation to unfold.

The National Transportation Safety Board (NTSB) has sent investigators. NTSB will share some early details in a press conference soon and usually release a preliminary report within a month.

At the moment, Atmos Energy claims it did not have anything to do with the explosion, but that is hard to stomach since it sounds like it was gas from its pipeline.

Atmos has a history of incidents throughout Texas and other parts of the Gulf South that have resulted in fatalities and injuries. Just eight years ago, in Dallas, a 12-year-old girl was killed in her house when it blew up from an undetected gas leak from an Atmos Energy pipeline.

https://www.dallasnews.com/news/article/how-struck-gas-line-caused-oak-cliff-explosion-22282784.php

How a ruptured gas line may have caused the Oak Cliff explosion A gas line was reportedly struck near an Oak Cliff apartment and may have leaked into the building, causing an explosion.