May 27 (UPI) -- The death toll from the mass shooting at a Northern California light rail yard increased to 10 Thursday, including the gunman, after one of the injured died in the hospital overnight, the medical examiner's office said.
The attack occurred at the Valley Transportation Authority in San Jose on Wednesday. Eight people died immediately. The gunman also died, police said.
The additional victim added to the death toll was 49-year-old Alex Ward Fritch. The Santa Clara County Office of the Medical Examiner-Coroner identified the other victims as Paul Delacruz Megia, 42; Taptejdeep Singh, 36; Adrian Balleza, 29; Jose Dejesus Hernandez, 35; Timothy Michael Romo, 49; Michael Joseph Rudometkin, 40; Abdolvahab Alaghmandan, 63; and Lars Kepler Lane, 63.
All the victims will be honored Thursday night at an event at the San Jose City Hall Plaza.
Investigators on Thursday will try to determine why VTA maintenance worker Samuel James Cassidy, 57, shot nine co-workers and then killed himself. Those killed were located in two buildings in the complex.
The attack was the deadliest mass shooting in the history of the San Francisco Bay Area. San Jose is located about 40 miles southeast of downtown San Francisco.
San Jose Mayor Sam Liccardo told CNN the victims "knew the shooter well."
Santa Clara County Sheriff Laurie Smith told CNN that Cassidy fired off 39 rounds and appeared to target specific victims. During the shooting, Cassidy told a union official present for a meeting, "I'm not going to shoot you," she said.
Smith said Cassidy had two semi-automatic handguns -- "the type that would be legal in California" -- and 11 loaded magazines in his possession.
Officials said Cassidy's home was on fire Wednesday morning after he left for work, and was fully engulfed when firefighters arrived.
During an appearance on NBC's Today show, Smith said authorities believe Cassidy may have set a timer to trigger the fire at his house.
"What we're operating under now -- but I'm not sure that this isn't gonna change -- is that he set some kind of a device to go off at a certain time probably to coincide with the shooting," she said.
Deputy Russell Davis of the Santa Clara County Sheriff's Office said the shooting happened as employees from the midnight shift were leaving and the day shift was beginning work.
Santa Clara County District Attorney Jeff Rosen told reporters that multiple guns were used in the shooting and some other suspicious items were found at the rail yard. The bomb squad ultimately cleared the scene.
In a 2009 court filing, an ex-girlfriend accused Cassidy of rape and said he would exhibit "enraged" mood swings that were fueled by alcohol.
Neighbor Doug Suh described Cassidy as "lonely" and said he'd never seen any friends or family visit in the five years he lived nearby.