The capture of an arms shipment from Syria, bound for Gaza, revealed attempts by Hamas to obtain advanced capabilities with which to threaten Israeli shipping and natural gas installations in the Mediterranean.
The German-owned Victoria, a container-ship on a routine voyage through ports in the eastern Mediterranean, took on a shipment in the Syrian port of Latakia on Monday.
On Tuesday morning, as the ship steamed south to Alexandria, it was boarded by Israeli naval commandos, 200 nautical miles west of the Israeli coast.
In three of the containers, under sacks of lentils and bales of cotton, they found what they were looking for. Along with more traditional military hardware, mortars and Kalashnikov bullets, they found six new C-704 anti-shipping missiles.
The advanced missiles, of Chinese design and made in Iran, were packaged along with two computerised command stations, two hydraulic launchers and two British-made small coastal radar systems.
The radar-guided missiles, which have a range of over 20 miles, "could have threatened the ships of the Israeli Navy, civilian shipping and some of the natural gas drilling platforms off our coast," said Major General Eliezer Marom, who was in charge of the operation.
"You can call this a weapon that changes the strategic balance."
For the past decade, Israel has been fighting a mainly covert war against Iran's attempts to smuggle arms to both Hizbollah in Lebanon and Hamas in Gaza.
These shipments in recent cases originated mainly from the port of Bandar Abbas in the Arabian Gulf, coming through the Red Sea and the Sudanese desert.
The new route, from Syria and then on to Egypt, proves Israeli success at blocking the Red Sea route. But it also raises concerns within the Israeli defence establishment, who have concluded that Iran and its allies believe that, with the Mubarak regime gone, it will be much easier to smuggle arms through Egyptian territory.
At a press conference at Ashdod Port where the ship was brought, Prime Minister Benjamin Netanyahu said: "This is the answer to all those who questioned, attacked and criticised our decision to stop and search ships bound for Gaza.
"The answer has been given today here in Ashdod in the clearest fashion. It is not only our duty, but our right to stop these boats and remove the weapons.
These weapons originated in Iran, and were meant for the terrorists in Gaza, but their target was the people of Israel."
Spokesmen for the Iranian Foreign Ministry and Hamas denied the Israeli accusations, saying that there was no shipment of arms from Syria to Gaza.
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