Muni door suddenly flies off while moving in San Francisco

SAN FRANCISCO (KGO) -- Muni has issued an explanation as to why a door suddenly fell off a light rail train.

Rider James Chang tweeted photos showing the car without a door. He says it flew off on Tuesday as the train traveled the tunnel between the Castro and Church Street stations.

Muni Director John Haley says the end cap that keeps the door's rollers in place became damaged through normal wear and tear, allowing the door to slide off.

Haley says nothing like this has happened in more than a decade.

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