By Walt Hunter

PHILADELPHIA (CBS) — SEPTA officials are warning 120,000 daily riders on regional rail lines that the threat of a strike at 12:01 a.m. Saturday is a growing possibility.

“It appears at this time they are preparing for a work stoppage,” SEPTA spokesperson Jerri Williams told reporters.

READ: SEPTA Regional Rail Service Interruption Plan In Event Of Strike

Two unions that work on Regional Rail trains have continued on the job for four years without a contract.

Steve Bruno, the national vice president for one of the unions, the Brotherhood of Locomotive Engineers and Trainmen, told CBS 3, “A strike is a virtual certainty. This strike is going to go forward unless there is a settlement.”

SEPTA riders say they are making alternate plans including carpooling, working from home and using City and Frontier Division trolleys and buses, since those unions will stay on the job despite the strike.

President Obama could order federal action that would keep workers on the trains, but it must first be requested by Governor Corbett.

The Governor’s Press Secretary is not indicating when — or if — he will act, stating only, “The Governor is encouraging both parties to continue to have productive discussions. The riders rely on SEPTA and deserve the effort to come to an agreement.”

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