Cleveland Circle explained. From Boston.com:

MBTA police are investigating the defacing of 14 Green Line trolley cars at the Reservoir Yard in Brighton. ... Nine of the cars have been cleaned and returned to the tracks, Pesaturo said. He said that service was not affected because the T owns a surplus of Green Line cars.

One thing about Mr. Pesaturo. He sure can tell a convincing fib with the best of them.