Vessel #2 was heading north on the colorado river from lake havasu on the right (arizona) side of the navigable portion of the waterway.  Once in the river, vessel #1 was observed heading south also on the arizona side of the navigable portion of the waterway.  The operator of vessel #2 turned to the right as vessel #1 was headed directly towards him.  At this time, vessel #1 turned the same direction.  Vessel #2 then turned to the left and vessel #1 did the same.  The operator of vessel #2 then throttled back and turned hard to the right and narrowly avoided a collision with vessel #1.  This hard turn to the right resulted in vessel #2 going into the tulies which line the arizona side of the waterway in this area.  The vessel then lurched back to the left causing the passengers to be thrown within the vessel.  As a result of the abrupt movement, several persons onboard vessel #2 were injured and the interior of the vessel was damaged.  Vessel #1 left the scene having never stopped.  Vessel #1 is still unidentified.
Lake Havasu City, AZ