Petaluma Police are investigating a traffic fatality that took the life of a bicyclist. Wednesday shortly after noon, police say a cyclist was struck by a Semi Truck on the 1000 block of Lakeville Street. Talking to witnesses and two truck drivers, including the driver of the semi involved, Both the bicyclist and the semi were traveling eastbound on Lakeville Street towards the 101 freeway at the time of collision. Cause of the collision, however, remains under investigation but it was noted that there is no indication that alcohol was a factor. The identity of the victim is not being released at this time pending notifications by the Coroner’s Unit.