Update: Explosion Rocks Area Of Calaveras County

Update at 10 a.m.: CAL Fire reports that the blast in Mountain Ranch did not spark a fire in the vegetation by the building that exploded. There also remains no word on what type of building or whether anyone was inside. Fire crews will remain on scene mopping up for several hours as investigators are actively trying to determine what ignited the explosion. Further details on the blast can be viewed below.

Original post at 9:25 a.m.: Mountain Ranch, CA — Emergency personnel is on the scene of a reported explosion in the Mountain Ranch area of Calaveras County.

The loud blast was heard by several neighbors who called 911. The explosion is in the vicinity of the 6700 block of Quartz Mine Road off of Swiss Ranch Road near Railroad Flat Road. There are few details being released, but CAL Fire is reporting that a building has exploded. There is no word on what type of building or whether anyone was inside or if the flames have spread to nearby vegetation. We will bring you more details as soon as they come into the news center.