Calling such a group "Israeli Defense Forces" makes as much sense as calling the occupiers of Iraq and Afghanistan the "Department of Defense". What the hell are any of these people DEFENDING?
Pacific Free Press has a report of possibly three dead . Gaza Freedom March says three dead and 30 wounded . Haaretz has this headline: "Report: Several casualties in clash between Gaza aid flotilla, Israel Navy"  but if it related to anything in the article, that part of the article has been censored.
Witness Gaza has Tweets  that include:
Report from IHH boat..two killed, 31 wounded. No verification but medical emergency can be seen from ship
Israeli soldiers shooting at people, all over the Turkish boat. Watch IHH streaming video
Israeli soldiers shooting unarmed civilians.
Live images from the IHH ship, wounded civilians: http://www.livestream.com/insaniyardim 
Several casualties in clash between Gaza aid #flotilla, Israel Navy: http://bit.ly/9ArSa0