SAN ANTONIO – The National Transportation Safety Board (NTSB) continues its investigation into a pair of North Side home explosions that injured five people, including a child. This shifts the investigation from a local emergency response to a federal safety probe.
KSAT previously reported that the explosions happened on April 21 at two separate homes in the same neighborhood, about two hours apart. Several people were hospitalized, and nearby homes were damaged, prompting evacuations in the area.
>> What we know about the North Side home explosions that hospitalized 5
As of Wednesday, April 22, NTSB investigators stepped in to lead the case. As of now, their report is in the preliminary stages as they continue to collect evidence.
Why the NTSB is involved
The NTSB is best known for investigating plane crashes and aviation disasters. However, the federal agency also examines major pipeline and infrastructure incidents involving natural gas or hazardous liquids during transport.
The agency’s involvement in this particular case typically signals a more complex investigation focused on identifying safety issues and preventing similar events in the future.
Officials note that the NTSB does not investigate every pipeline incident, but steps in for more serious cases that may have broader safety implications, such as fatalities, substantial property damage or significant injury to the environment.
How the investigation works
According to the agency, the investigation will focus on three primary areas: human factors, the pipeline system and environmental conditions.
That includes reviewing operator training and performance data, pipeline pressures and maintenance records, and environmental aspects such as soil and weather at the time of the explosions.
Investigators will also collect pipeline maps, historical records, and operational data from monitoring systems, along with witness statements and any available surveillance video, including doorbell camera footage.
During this early, on-scene phase, the NTSB tells KSAT it does not determine or speculate about the cause of the explosions. Instead, investigators focus on gathering what they describe as “perishable evidence” and building a factual timeline of events.
What happens next
The preliminary report is expected within about 30 days and will include factual information gathered during the initial phase of the investigation.
A final report, including the probable cause and any contributing factors, could take 12 to 24 months to complete.
NTSB adds that it does not assign blame, release victim identities or assess property damage. Those responsibilities remain with local authorities.
How the public can help
Investigators are asking anyone who witnessed the explosions or may have relevant video or information to email NTSB at witness@ntsb.gov.
The agency said it will provide updates on the case through its website and its X account as new information becomes available.
KSAT continues to follow updates on the Preston Hollow home explosions. Read more of our coverage below: