A Permanente Quarry employee killed two people and injured four others after opening fire at the Cupertino cement mine in Northern California this morning, ABC News is reporting. Santa Clara County sheriff’s officials have confirmed the shooting, and that the suspect is still at large.

Joy Alexiou, the spokeswoman for the Santa Clara Valley Medical Center, has said the hospital is treating two of the injured victims. The two are reportedly in good and fair condition, but their names and the extent of their injuries have not yet been released.

The Stanford University Medical Center in Palo Alto has received one of the other surviving victims, spokeswoman Paula Zimlicki has confirmed. However, she added that she can’t release any details about the patient or their injuries.

No detals about where the remaining victim is being treated have been released. Officials have also yet to release any information about the suspect’s motives in the shooting at the limestone and aggregate and mining operation and cement plant.

But several SWAT teams have been dispatched to Permanente Quarry to search for the suspect. The gunman reportedly became upset during a shift change meeting at 4 am PST.

Written by: Karen Benardello