Reports are still sketchy, but the word is 2-3 dead after Israeli missile boats attempted to board ships trying to bring in various goods and aid to the Gaza Strip, in defiance of an Israeli blockade.
More as reports come in, and I don't want to prejudge when information is so scarce. But if this is what it sounds like, it is unacceptable behavior. You don't fire on an unarmed convoy, in international waters. I don't care how risible the Hamas regime that will receive the aid is, I don't care how suspect the motivations of the convoy organizers are, and I certainly don't think even justified fears over the misuse of cement, are good enough rationales to resort to a violent seizure. And I would bet that the (justified) international backlash over this will spell the end of the blockade anyway.
UPDATE: Okay, some new information coming in that sheds some additional light.
The IDF's official account of the incident is now up, the other main sources are here and here. Same caveats as above apply -- what we really have now are two sides to the story, not "the story".
1) The clashes apparently occurred on only one of the boats. Reports are that this boat represented a particular Turkish charity that was known as the most radical of the groups in the flotilla.
2) Israeli sources are claiming that the activists on the boat were armed with light weaponry (slingshots, clubs, bats, and knives, with conflicting reports about the possibility of pistols) and attacked the boarding commandos first. They're claiming they've got video to back up the assertion that the activists attacked the soldiers first, and soldiers fired back only to save fellow soldiers in mortal peril (and that these were the standing engagement orders for the operation).
I think this whole sequence of events can be broken down into several constituent parts. We can debate whether or not the flotilla was justified in trying to breach the blockade, rather than unloading in an Israeli port and transporting (most of) the goods by land. Even if we say they were not, we can still debate whether or not Israel was justified in commencing a boarding action to stop the flotilla. But again, even if they weren't, we can debate whether the activists had the right to violently resist the commandos. And finally, after that, we can ask whether the Israeli use of force was justified given that resistance.