There were no passengers aboard at the time, and the female bus driver was seen leaving the bus moments before it rolled away.
Police say 10 cars were also struck by the bus and damaged.
Police say the driver of the bus got out of the vehicle around 12:30 a.m. Wednesday in Bushwick, but left it in neutral. One man who was attempting to change a tire on the street was forced to jump out of the way.
The bus finally came to a stop when it rammed into St. Paul's Evangelical Lutheran Church, damaging metal fencing and a brick column. A suspected tire - or tire iron - hit him as the bus rammed a vehicle.
The accident comes on the heels of extended and increasingly severe delays on New York's aging subway system, another black-eye for which the MTA has publicly apologized.
"They said I don't know, something with the brake".
Paul Quiroz, 46, was watching TV in his home on Knickerbocker Avenue when the bus started to roll away.
No charges were immediately planned for the driver, but the incident is still under investigation, police said.