An employee of a California transit agency opened fire Wednesday morning at a San Jose, California, light railyard, killing eight people before reportedly taking his own life.

Watch a replay of the latest news conference from San Jose:

According to the Santa Clara County Sheriff’s Office, the suspect has only been identified as an employee of the Valley Transportation Agency.

However, numerous media outlets are reporting the suspect’s name is Samuel Cassidy, 57, who is also being reported as taking his own life at the scene.

According to Santa Clara County sheriff’s spokesman Deputy Russell Davis, officers responded about 6:30 a.m. PT to multiple 911 calls regarding shots fired at the Valley Transportation Agency facility, which also includes a maintenance yard. The shooting happened around the time of a shift change.

Davis also confirmed the suspected shooter is dead, though no cause of death details have been officially released. Police also have not released the type of weapon used by the shooter. The victims were all Valley Transportation Authority employees, Davis said.

No details have been released regarding the identities of the victims. One is reported to be in critical condition at a local hospital.

Cassidy’s home was also the scene of a heavy law enforcement presence early Wednesday, when authorities responding to a house fire reportedly found empty gas cans and the smell of gasoline. A local NBC reporter said hundreds of rounds of ammo were found throughout the house.

“A horrible tragedy occurred today,” said Glenn Hendricks, chairman of the VTA board of directors, who added the shooting happened in the train yard.

“This is a horrific day for our city,” said Mayor Sam Liccardo during the second media briefing Wednesday. “We are in a very dark moment.”

The VTA provides bus, light rail and other transit services throughout Santa Clara County, the largest in the Bay Area and home to Silicon Valley. Hendricks said all light rail service was being suspended for the rest of the day, but buses were still going to continue running.

“These folks were heroes during COVID 19, the buses never stopped running, VTA didn’t stop running. They just kept at work, and now we’re really calling on them to be heroes a second time to survive such a terrible, terrible tragedy,” Santa Clara County Supervisor Cindy Chavez said.

Gov. Gavin Newsom said in a tweet that his office was “in close contact with local law enforcement and monitoring this situation closely.”

VTA trains were already out on morning runs when the shooting occurred.

Outside the scene, Michael Hawkins told The Mercury News that he was waiting for his mother, Rochelle Hawkins, who had called him from a coworker’s phone to assure him that she was safe.

When the shooting started, “she got down with the rest of her coworkers” and dropped her cellphone, Michael Hawkins told the newspaper. Rochelle Hawkins did not see the shooter, and she was not sure how close she had been to the attacker, her son said.

Special agents from the FBI and the federal Bureau of Alcohol, Tobacco, Firearms and Explosives were responding to the crime scene, officials said.

Investigators offered no immediate word on a possible motive.

Santa Clara County District Attorney Jeff Rosen said it was his understanding the shooting happened during a meeting.

Grief-stricken families sat huddled together, holding hands and crying, after learning they had lost a loved one, Rosen told reporters, describing the scene inside a county building.

“They’re just sitting and holding hands and crying,” Rosen said. “It’s terrible. It’s awful. It’s raw. People are learning they lost their husband, their son, their brother.” He said about 100 people were inside the family reunification center.

Bomb squads were searching the rail complex after receiving information about possible explosive devices, Davis said.

Cassidy had worked for the VTA since at least 2012, according to the public payroll and pension database known as Transparent California. His position from 2012 to 2014 was listed as a mechanic. After that, he was a substation maintainer, the records said.

Newsom spoke emotionally in front of a county office where flags flew at half-staff. He said victims’ relatives were “waiting to hear from the coroner, waiting to hear from any of us, just desperate to find out if their brother, their son, their dad, their mom is still alive.”

The bloodshed comes in a year that has seen a sharp increase in mass killings as the nation emerges from pandemic restrictions that closed many public places and kept people confined to their homes.

A database compiled by The Associated Press, USA Today and Northeastern University that tracks every mass killing during the last 15 years shows that the San Jose attack is the 15th mass killing so far in 2021, all of them shootings.

Eighty-six people have died in the shootings, compared with 106 for all of 2020. It is the sixth mass killing in a public place in 2021. The database defines mass killings as four people dead, not including the shooter, meaning the overall toll of gun violence is much higher when adding in smaller incidents.

At the White House, President Joe Biden ordered flags to be flown at half-staff and urged Congress to act on legislation to curb gun violence.

“Every life that is taken by a bullet pierces the soul of our nation. We can, and we must, do more,” Biden said in a statement.

San Jose, the 10th-largest city in the U.S. with more than 1 million people, is about 50 miles south of San Francisco in the heart of Silicon Valley.

In the city itself, the most recent mass shooting occurred in 2019 at a private home, according to The Mercury News. Police said it was a quadruple murder and suicide precipitated by family conflict.

Wednesday’s attack was the county’s second shooting in less than two years. A gunman killed three people before killing himself at a popular garlic festival in Gilroy in July 2019.

The Associated Press contributed to this report.