(KMOV) -- A St. Louis Metro bus caught fire in Maplewood Thursday morning, but the driver and three passengers were able to get off the bus safely.
Firefighters responded to the scene in the 7600 block of Folk after a fire started in the Metro's No. 2 Red Line bus around 6:30 a.m.
Police say the Metro bus was preparing to make a stop when there was a muffled boom near the rear of the vehicle.
The driver tried to put out the fire but couldn't. An investigation into the cause continues.