Despite pleas for information from Orange Line riders on its social media pages during Thursday and Friday morning rush hours, the agency offered no explanation.

Several hours after an inquiry from the Globe on Friday, MBTA spokesperson Lisa Battiston published a statement saying that the T had found a “failure in a power cable that may have created some electrical arcing with a nearby train axle” on one of the Orange Line cars during a recent inspection. Further inspections found the issue on nine cars.