Metro bus and rail service returned to normal operations Saturday following Friday's "sick-out" by bus drivers in response to concerns about their safety on the transit system.
"Metro remains grateful to our operators who remain the backbone of our agency," Metro spokesman Jose Ubaldo said Saturday.
Metro issued alerts to riders throughout the morning Friday warning of possible "significant delays" on select bus lines "due to staff shortages."
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"Bus operators are the face of Metro to more than 80% of Metro riders," the transit agency said in a statement. "They are the lifeblood of the Metro organization. We understand their and their families' fear in the face of the senseless assaults some have experienced primarily resulting from the twin crises of untreated mental illness and drug addiction.
"We share their frustration and have expedited the installation of barriers to keep them safe, as well as the re-deployment of safety and security personnel on board buses to deter assaults. At the same time, we are working on longer term plans, which include the addition of even more dedicated transit security bus riding teams."
A series of recent crimes have involved attacks on Metro bus drivers.
A Hawthorne man who allegedly stabbed a Metro bus operator in the chest in the unincorporated Willowbrook area on April 13 pleaded not guilty on April 29 to an attempted murder charge.
The case against Darnell Marshon Bray, 30, includes allegations that he used a knife during the crime and personally inflicted great bodily injury, according to the Los Angeles County District Attorney's Office.
The Metro bus operator was driving his bus route "when the suspect started yelling at him," according to a statement released by the Los Angeles County Sheriff's Department.
Following those attacks and the death of a woman who was stabbed on the Metro B (Red) Line subway in Studio City, Metro officials expedited efforts to acquire and install protective barriers for drivers on thousands of buses, while also exploring other safety upgrades throughout the system.
Metro's Board of Directors on April 29 approved an emergency procurement declaration to speed up acquisition and installation of barriers for about 2,000 buses due to the "sudden, unexpected increased severity of assaults on operators."
Metro said in its statement that riders in Los Angeles County depend on the Metro bus and rail network every day "to reach critical destinations including work, school and medical facilities."
"We appeal to our operators to reconsider the impact their plan to call in sick will have on some of the most vulnerable people in the county," the statement read.
"Transit operators who intentionally plan to call in sick put our customers at risk. Further, it is a violation of Metro's Collective Bargaining Agreement, so we hope they will reconsider."