Hazmat incident in Daly City possibly linked to San Francisco house explosion

A box truck that picked up evidence from a home that exploded in San Francisco on Thursday appears to be the focus of the hazardous materials investigation in Daly City on Friday.

The white box truck seen near Junipero Serra Boulevard, south of John Daly Boulevard in Daly City was seen earlier Friday in San Francisco's Sunset district at the site of house fire and explosion that killed one person. 

It's unclear if the truck made any other pickups or deliveries before the hazardous materials situation began unfolding. 

The left side of the image shows a white box truck that is the focus of a hazmat investigation in Daly City on Friday. The right side of the image shows that same box truck hours earlier at a home in San Francisco's Sunset District that was the site

The driver of that truck reported hearing a loud noise accompanied by the smell of gas, according to North County Fire Marshal Craig Whitner. 

Inside the truck were several cylinders carrying an unknown type of gas, said Whitner.

Hazardous material teams and a bomb squad unit responded to the scene in Daly City to try and determine the type of gas and how to treat it.

The Daly City BART station was evacuated, and two other stations were closed around 10:15 a.m. Friday. BART service was restored after several hours.

The southbound 280 off-ramp to John Daly Boulevard was closed, but the highway remained open, according to the California Highway Patrol.

Video from the scene shows several fire trucks along Junipero Serra Boulevard, south of John Daly Boulevard.