It happened at Madison Avenue and 85th Street around 7:05 p.m.
"I looked up and I saw him swerving to the right and he's hitting cars," said Leslie Bautista, a passenger.
It took a few seconds for passengers to realize what was going on.
Their bus driver blacked out behind the wheel with 23 frightened people on the out-of-control bus.
"We heard some screams and lots of loud thuds, but lucky we had lots of green lights, but it felt like we blew through about seven intersections," said Becky Lubin, a passenger.
Passengers pried the wheels from the driver's hands and managed to stop the bus suddenly at East 85th and Madison Avenue.
"I tried to hit the break. I couldn't because he was sitting there. I figured his leg was on the gas. So I moved his leg and the bus stopped, it slowed down," said Guy Praisler, a passenger.
"I pulled him away from the wheel. Another gentleman started steering the bus. We hit a bunch of stuff along the avenue. The driver woke up and hit the break," said Arkady Kerkovitch, a passenger.
One passenger was taken away in an ambulance suffering from minor injuries.
Passengers say the BXM18 driver suffered some sort of medical condition and they just hope he's OK.
"I just feel really bad for the driver he's probably the nicest one," Praisler said.
Six people total went to Lenox Hill Hospital; four that were on the bus and two others not on the bus. The injured people not on the bus included a driver of a car that was struck and a person in a taxi cab.
All have non-life threatening injuries.