Body cam video shows moment officers respond to VTA mass shooting

Almost one week after a disgruntled Valley Transportation Authority employee carried out a deadly mass shooting at a rail yard where he worked, authorities released body-worn video of law enforcement officers' quick response to the active shooter scene.

What was supposed to be an ordinary workday for VTA workers last Wednesday turned tragic after nine employees lost their lives in what is now the Bay Area's deadliest mass shooting.

On Tuesday, the Santa Clara County Sheriff's Office on Tuesday etched out a clear timeline of what unfolded when law enforcement officers arrived at the rail yard and closed in on the suspect.

A sheriff sergeant, deputy, and three San Jose police officers got to the scene within minutes of receiving the first 911 call at 6:34 a.m.

SEE ALSO: Gunman appeared to target some victims at VTA light rail yard in San Jose

The sergeant and officers immediately formed a tactical plan to make entry into the building.

Video shows officers entering Building A at the rail yard, which is considered a hot zone as the area poses a direct threat to the public, the sheriff's office said.

At 6:41 a.m. two shots are heard as the contact team goes up a stairwell that leads to the third floor of building A. The sheriff deputy and sergeant take the lead as the contact team reaches the third floor when they see a VTA supervisor escaping through a door. The VTA supervisor provides officers with his key card so they could move about the building.

"Come behind me, come behind," officers can be heard instructing the VTA supervisor to follow their lead.

Once officers get inside the building, they move from room to room searching for the shooter or any victims when they hear gunshots.

SEE ALSO: Remembering the San Jose VTA shooting victims

The body-worn footage shows the suspect, later identified as 57-year-old Samuel James Cassidy, slumped over in a chair with a gun. Authorities determined that Cassidy shot himself twice, which proved to be fatal.

Authorities said evidence shows that the suspect fired at least one shot toward the officers, but none of them were harmed. 

The video ends moments after officers spot Cassidy's body, which was redacted in the video.