A hazardous materials investigation in Daly City that forced closures of several BART stations Friday involved items tied to an explosion in San Francisco's Sunset District, firefighters said.
The driver of a truck carrying evidence from the explosion pulled over near a BART track overcrossing in Daly City because he heard a hissing sound, San Francisco Fire Department Capt. Jonathan Baxter said.
The driver called 911 after seeing one of the items being transported started to leak, sparking a hazardous materials investigation and the evacuation of the Daly City BART station.
BART's Balboa Park, Daly City and Colma stations were shut down during the investigation and reopened later in the afternoon.
Emergency crews during the response set up a perimeter outside the Daly City station and said the entire intersection of Junipero Serra and John Daly boulevards were closed to traffic.
Baxter said that the hazardous materials investigation was resolved around 3:30 p.m. and the evidence was transported to its original destination.
Thursday's explosion in San Francisco was followed by a fire along the 1700 block of 22nd Avenue. It left one person dead and two injured, firefighters said.
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