The National Transportation Safety Board met on Sept. 24, 2019, at 9:30 a.m. (EDT), to determine the probable cause of the Sept. 13, 2018, series of explosions and fires in the Merrimack Valley in Massachusetts.

The explosions and fires occurred after highpressure natural gas was released into a lowpressure gas distribution system in the northeast region of the Merrimack Valley. The system overpressure damaged 131 structures, including five homes that were destroyed. Most of the damage was a result of structure fires ignited by gasfueled appliances. One person was killed and 22 individuals, including three firefighters were transported to area hospitals.

The urgent safety recommendations issued earlier in the investigation are available at https://go.usa.gov/xVx73.