Hours after we learned of the shooting in San Jose that claimed the lives of eight Valley Transportation Authority (VTA) workers, we're hearing more details about the man believed solely responsible — who also took his own life.

In a portrait that will likely kindle the ongoing national debate over so-called "red flag" laws, 57-year-old Sam Cassidy reportedly suffered from mental illness and severe mood swings, according to an ex-girlfriend. And while a motive in the rail yard shooting is not yet known, it is beginning to sound likely that co-workers or family members may have had warning signs.

As KPIX reports, Cassidy was employed by the VTA as a substation maintainer, and public records show that he earned $114,000 in regular and overtime pay as well as an additional $46,000 in benefits in 2019. He owned a home on the 1100 block of Angmar Court which was apparently set ablaze Wednesday morning shortly before he arrived at work at the rail yard on West Younger Avenue — or some incendiary device had been planted there. The shooting began around 6:34 a.m., and Cassidy's home, which is a ten-minute drive from the rail yard, was reported on fire just moments later, or simultaneous with the first shots.

The shooting reportedly took place during a morning meeting at what is called the Guadalupe maintenance yard.

Authorities say they found explosives, ammunition, and gasoline throughout the home, and evacuated the block as a precaution as they secured these items. Still, the home was apparently rendered uninhabitable.

There were also early reports of explosives at the VTA site, but those have not been clarified. And there was a second fire that's being attributed to Cassidy, a structure fire on the 1800 block of Smith Avenue, at a plywood and lumber business. That was reported at 6:29 a.m.

The Chronicle dug up a sworn statement filed by an ex-girlfriend of Cassidy's in 2009, which she filed in response to a domestic violence restraining order he filed against her. In the statement, she denied Cassidy's allegations about any threat she posed, and said that he suffered from bipolar disorder that was worsened when he drank heavily.

She also told a story about a trip to Monterey that she was supposed to take with Cassidy before they broke up around Valentine's Day in 2009. She says that Cassidy said he would only agree to the trip if she agreed to have anal sex with him.

The woman, who is not being named because she was a victim of sexual assault, alleged that Cassidy had more than once become intoxicated and forced himself on her. She was 45 at the time of the complaint, so about the same age as Cassidy, and she is described as being 5-foot 4-inches and 120 pounds. He was described as 6-foot 1-inch and 200 pounds.

Cassidy accused the woman in his restraining order of vandalizing his property, surveilling him, and threatening to try to get him fired. He filed the restraining order to protect himself, a female roommate and his family, he said.

The woman claims that Cassidy's "mood swings" resulted in violent behavior, and she also said he "played several mind games which he seems to enjoy."

KTVU reports that Cassidy has an ex-wife whom he apparently divorced in 2009. They also spoke to the mother of a coworker of Cassidy's who said her son thought he was "strange."

Related: Mass Shooting Kills at Least 8 Victims at Downtown San Jose VTA Train Yard