OAKLAND (CBS SF) — East Bay commuters have more than just a potential Bay Area Rapid Transit strike to worry about Monday morning.

AC Transit issued a warning Saturday evening urging passengers to consider transit alternatives for Monday as contract talks with employee unions had so far failed to result in either a new contract or an extension of the existing contract, according to spokesman Clarence Johnson.

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The AC Transit union’s contract expires on Sunday night, the same time as contracts between BART and its five unions end. AC Transit employees voted overwhelmingly last week to authorize a strike as soon as Monday, so the clock is ticking.

Amalgamated Transit Union Local 192 President Yvonne Williams has cited worker safety and plans to replace sheriff’s deputies assigned to ACTransit with private security guards as primary union concerns in the negotiations.

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The warning from AC Transit follows on the heels of a statement from BART unions Saturday that they intended to strike Monday. Union leadership walked out of contract talks earlier today, arguing that BART officials had employed stalling tactics.

AC Transit officials have said that in the event of a BART strike they would try to provide additional transbay service where possible, but union officials had warned that AC Transit does not have sufficient additional capacity to absorb large numbers of BART riders.

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