A CTU bus driver allegedly slapped an auto-rickshaw driver which led to a traffic jam near the Sector 27/19 light point on Wednesday afternoon. The driver of the CTU bus hit an auto from the rear when the latter reportedly did not move his vehicle from the designated bus-stop in Sector 19. This led to a heated argument between the bus and auto driver. During the argument,the bus driver slapped the auto-rickshaw driver. The incident led to a traffic jam for over 15 minutes as two CTU buses,present on the spot,blocked the road. The situation was brought under control after Sector 26 police personnel reached the spot.