Who ordered commandos to use live ammunition on a ship of activists heading for Gaza? The answer needs to be given immediately, because what happened in the waters off Palestine early on Monday cannot be tolerated.

There was already much anxiety about the journey. The Free Gaza Movement, one of the organisations behind the trip, had sent five previous aid convoys to Gaza, and while the first two had got through, the next three missions had been intercepted in Israeli waters. The Israelis had warned that they would not tolerate what their foreign minister described as a "violent propaganda attack". This time they had committed not to allow the ships to enter the 20-mile zone off Gaza.

The accounts of what happened that are emerging do not, unsurprisingly, tally. According to the Israelis, they gave a warning, went on to the ship and came under attack from the activists, who used "live fire and light weaponry including knives and clubs". In another statement, they claimed that the "Israel Defence Forces (IDF) apprehended twoviolent activists holding pistols. The violent activists took these pistols from IDF forces and apparently opened fire on the soldiers as evident by the empty pistol magazines."

Activists, for their part, describe a surprise invasion while most were sleeping, with the commandos beginning to shoot the moment their feet hit the deck and firing directly into groups of civilians. Footage shows that fighting broke out as the commandos landed. Chaos follows. In an al-Jazeera news report, filed under fire, an announcer tells the inhabitants of the boat: "Don't show resistance, they are using live ammunition. We cannot protect ourselves." The sheer terror in his voice - with one agonised pause after a particularly loud bang goes off - is heartbreaking.

Now what? The confirmed death toll at this point stands at nine. Already some countries are taking action; Turkey has recalled its ambassador to Israel, and demonstrations are taking place outside the Israeli embassies in at least 40 countries. The United Nations has already held an emergency meeting to discuss the events.

Clare Solomon, of the left-wing news and analysis website Counterfire, says this exposes to public view the way in which Israel has been behaving for years. "Israel is a terrorist state," she says, "that has systematically targeted and killed anyone it considers to be an enemy. The psychotic nature of its behaviour is out in the daylight here; the world's governments really have to act, and act now."

With the blockade of Gaza, mounted since 2007, Israel, under the guise of controlling the "terrorist" Hamas government, has restricted
the movement of people and goods in and out of the tiny Palestinian area. It has long been condemned as a "collective punishment" of the Palestinian people (the UN's words, not mine). And yet, the Israeli government has been allowed to get away with it. The activists set out on their ships to expose this and force the international community to admit that we are covering up for Israel's criminal actions in Gaza. They will have known that their lives were at risk, but will have hoped it would not come to that. Now that it has, we need to make good on what they have done.