"All the cargo certificates are stamped at the ports of origin, and this one was stamped at an Iranian port."
'Tons' of weapons
Israeli commandos boarded the ship before dawn in the waters near Cyprus.
Rear Admiral Roni Ben-Yehuda, the deputy Israeli navy commander, told a briefing that "hundreds of tons" of weapons were found.
His estimate was much higher than an earlier one of more than 60 tons.
The weapons were "a drop in the ocean" of arms being shipped to Hezbollah, Ben-Yehuda said.
But hours after the seizure, Israel had not provided evidence that the arms were meant for the Lebanese guerrillas.
Speaking at a news conference in the Syrian capital, Damascus, Walid al-Muallem, Syria's foreign minister, said the ship was carrying civilian goods from Syria to Iran.
|The weapons were in ordinary shipping containers, according Israeli officials [AF]
Al Jazeera's Jacky Rowland, reporting from Jerusalem, said: "It's interesting to point out the timing of this announcement.
"The fact that the Israeli army chose to hold the press conference exactly the same time as the UN General Assembly was beginnning its debate on the Goldstone report [on the Israeli war on Gaza].
"At the very least, the timing of this announcement was convenient. If one were cynical one could even suggest that actually the announcement was timed to, if anything, to distract some of the attention of the media in Israel from the Goldstone report."
The Israeli army insists that it was operating under existing international protocols for boarding and inspecting ships when it seized the vessel, our correspondent said.
Quoting officials who addressed a news conference after the seizure, Rowland said the weapons were in ordinary shipping containers hidden among hundreds of other containers on board the vessel.
"They say it was clearly an attempt to disguise the containers as ordinary civilian cargo," our correspondent reported.
No Hezbollah comment
A senior Lebanese army official refused to comment on the Israeli report, saying it happened outside Lebanon's national waters.
A Hezbollah official, speaking on condition of anonymity because he did not want to speak publicly to the media, said the group had no comment on Israel's claim.
"We are following the case and we will see if it is worth a comment," he said.
The ship seizure comes three years after Israel and Hezbollah fought a bitter war that ended with a UN-brokered ceasefire. Occasional clashes continue to occur.
The seizure was bigger than a similar haul in 2002, when Israeli military confiscated a vessel with 50 tons of missiles, mortars, rifles and ammunition headed for Palestinian fighters in the Gaza Strip.
Hezbollah, which has widespread support in southern Lebanon, was originally established to fight the Israeli occupation of the region.