Newly-released 911 calls offer a glimpse into a tragic crash of a van in California's Sierra Mountains.

In the chilling audio (you can hear in the video above), a woman tells the dispatcher, "We’re coming off of 80. We’re on a side road, we’ve lost our brakes, there’s eight of us."

The woman then said she did not know where they were located on the highway or which direction they were traveling.

The van ultimately crashed into a Volkswagen Jetta. The van then slid down an embankment and caught fire.

One person was killed inside the van, with six other people injured.

Authorities are not certain whether a stuck accelerator or brake failure was to blame.