LOS ANGELES (AP) — Federal safety investigators say operators of the historic Angels Flight funicular railway in downtown Los Angeles intentionally overrode a safety system before two cars derailed last month.

The National Transportation Safety Board issued an urgent recommendation Thursday that a series of safety issues be addressed before the reopening of the short railway.

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No one was hurt Sept. 5 in what was the latest accident on “the shortest railway in the world,” though six people had to be helped from the line’s two cars.

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In its report, the NTSB said the railway’s operators had broken off a tree branch and used it to permanently depress a button so that the cars would restart during unintended stops. These stops, a sign of problems on the line, were happening regularly before the accident.

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