The incident occurred on the Uriah Butler Highway at 1.20 p.m.
The bus was dispatched from Port of Spain at 1 p.m. and was heading to Chaguanas with 72 passengers on board.
Witnesses said the bus driver swerved to the right to avoid colliding with a vehicle that had stopped suddenly in front of it.
This resulted in the front of the bus facing west.
A baby and a young child were taken to hospital by ambulance.
Officials of the Corporation including Mr. Brian Juanette, Deputy General Manager Operations, Brian Juanette and Deputy General Manager Engineering, David Bartholomew are on the scene.
The PTSC said it will update the media when additional information becomes available.