SAN JOSE – The Valley Transportation Authority on Monday will begin running buses along part of its defunct light rail system.

The light rail system was taken offline after a disgruntled VTA employee opened fire at the system’s maintenance and dispatch facilities on May 26, killing nine co-workers before taking his own life. The mass shooting was the deadliest in Bay Area history.

The bus service will operate along First Street in San Jose, from the Paseo de San Antonio Station to Baypointe Station, then over to the Milpitas Transit Center along Tasman Drive, the VTA said in a news release.

The agency said the service will operate every 30 minutes on weekdays from 5:30 a.m. to 8:30 p.m. and hourly on weekends from 7 a.m. to 7 p.m. No fares will be charged until light rail service has been restored.

“At this time, there is no firm estimate of when light rail service will begin,” the VTA said. “VTA is working diligently and compassionately to ensure employees impacted by the tragic events of May 26 feel safe and confident to return to their normal duties.”

Agency officials previously said the public could be riding trains again by the end of July, but that estimate has been pushed back to mid-August. In a recent interview with this news organization, new General Manager Carolyn Gonot said the VTA first needs to bring back supervisors and managers, and complete track inspections.

“Because we have been down for a while this is required by the California Public Utilities Commission,” Gonot said. “The timing of bringing employees on is going to take a little longer. Many of them are ready to come back, (but) we need to have the resources and the tools for them to be able to be up and running.”