RedactedNarrative: Jet ski instructor from a rental company went over the 12 point safety instruction from Yamaha.  He brought them out of the harbor at idle speed.  Once clear of the jetties we all began to accelerate and spaced out.  They were told to stay between the green can marker and the end of the concrete wall and to stay 100 yards off the beach and each other.  He then sent them to ride in different directions when all of a sudden vessel #2 rushed up on vessel #1 and closed the safety gap in a matter of seconds.  Vessel #1 did not see vessel #2 coming at him and turned left and they collided.  Collision caused property damage as well as victim being ubhyred.  9/26/14 waiting for investigator for cause and property damage to vessel #2.  No property damage to vessel #2.  Operator of vessel #1 is at fault in this accident for crossing unreasonably close.  Officer is working with rental company to properly identify their PWC's when they are leased out to their customers.  10/10/14 Received information confirming machines involved in this incident.