PHILADELPHIA (WPVI) -- Three SEPTA employees have died from the coronavirus, Action News has learned.
SEPTA confirmed Tuesday the three employees were maintenance workers and worked at the Midvale, Southern and Elmwood depots.
Transport Workers Union Local 234 president Willie Brown said the Midvale employee, identified as Michael Holt, died Monday night, and was one of six positive cases out of that facility.
According to the union, Phillip Williams who worked at the Southern Depot died three days ago. There were four additional positive cases at that facility, Brown told Action News.
Theodore Nixon was an employee at Elmwood and died last week. He is among seven employees who have tested positive at that location, the union said.
SEPTA officials said they do not know where the three employees contracted the virus.
RELATED: New SEPTA safety measures in place during coronavirus crisis
Last week, it was reported at least 16 SEPTA employees had tested positive for COVID-19. They worked at various sites including the Comly Depot, the Norristown High-Speed Line Shop, Frankford Transportation Center, along the Market-Frankford Line, at the Allegheny Depot and the Elmwood Depot.
Brown said the Comly Depot has seen no deaths, but is a "hot spot" with seven employees testing positive for the coronavirus.
The transit agency has continued to add new safety measures to its line of trains, buses, and trolleys as the coronavirus outbreak spread throughout the Philadelphia region.
Starting on Thursday, SEPTA will move to a new "Lifeline Service Schedule," with limited service on all modes of travel.
Officials said the change is designed to provide core services for essential travel and to focus on cleaning efforts to protect the health and safety of our customers and employees.
SEPTA is asking all riders to wear masks or other facial coverings, consistent with new CDC guidelines. SEPTA has started issuing masks to all frontline employees.
Beginning last Wednesday, riders were instructed to board buses and trolleys in the back, with on board payment suspended. Riders with disabilities can still board through the front.
SEPTA has also limited the number of passengers on board to further promote social distancing.
RELATED: Social distancing: What is it, and how it slows spread of coronavirus
Other measures include additional cleaning and only using buses with protective shields.
More information can be found on their website.