ASHDOD, ISRAEL — Israel said on Wednesday that its Navy had intercepted a ship, some 100 miles offshore in the Mediterranean, carrying Iranian containers concealing more than 500 tons of weapons. The armaments, Israel alleges, were bound for Syria and eventually Hezbollah in Lebanon.

Israel's security services have recently alleged Hezbollah violations of the cease-fire deal that ended the 2006 between Israel and said that Hezbollah appears to be rearming for future conflict.

The Jewish state also accused Syria of serving as an intermediary for the arms shipments.

"This cargo is [further] proof of the ongoing efforts of Iran to support terror," said Brig. Gen. Rani Ben Yehuda. "It is clear that these terror weapons were destined for Hezbollah."

In Tehran, Syrian Foreign Minister Walid al-Moallem dismissed Israeli allegations that the ship carried arms, the Associated Press reported.

"Unfortunately, some official pirates in the seas, sometimes in the name of the Navy, sometimes in the name of inspection, obstruct trade movement between Syria and Iran," Mr. Moallem said at a joint news conference with his Iranian counterpart.

Military officials said one of their ships stopped the Antiguan-flagged Francop late Tuesday evening, during what they described as a routine patrol of the international waters off the Israeli coast.

After questioning the Polish captain, Israeli soldiers received permission to board the German-owned vessel and reviewed the ship's manifest, which showed about 40 of the boats 300 containers to be Iran Shipping Lines containers en route to Syria.

An inspection of some of the containers revealed wooden ammunition crates hidden amid sacks of industrial polyethylene. Following the discovery, Israel's navy escorted the boat to the port of Ashdod to inspect the rest of the cargo.

Ships cargo
Military officials said the crew was unaware of the cargo's contents, and speculated that port officials in Egypt also didn't know.

"Syria and Iran's grave actions violate all international laws," Israeli President Shimon Peres said in a statement. "The ship's arrest is not only of critical military importance, but also of political importance - facts cannot be argued with."

A spokesman for the United Nation's Interim Force in Lebanon (UNIFIL) charged with overseeing the cease-fire and stopping weapons shipments, said his organization had no information beyond what it had read in the press about the seizure. The group's mandate confines it to Lebanon's territorial waters. He said UNIFIL's position is that allegations that the weapons were destined for Hezbollah are "unproven."

On Wednesday afternoon, Israel's military had inspected only about one-third of the containers. As dock cranes reaching about 10 stories high moved containers with the letters IRISL - the marking of the Iranian shipping company -- reporters were allowed to inspect the cargo.

Some of the containers were partially unpacked to show weapons crates hidden amid the polyethylene sacks. Next to others were stacks of crates with 122-millimeter and 107-millimeter Katyusha rockets, 106-millimeter artillery shells, mortars, and bullets.

General Ben Yehuda said the weapons originated in the Iranian port of Bandar Abbas. The shipment was picked up by the Francop in Damietta, Egypt. From there, the boat was scheduled to make stops in Limassol, Cyprus, and in Beirut before reaching Latakia, Syria.

Ben Yehuda described the shipment as "huge," with "quality" weaponry, but claimed it was but a "drop in the sea."

Military officials said the Navy and Air Force have stopped ships in the Mediterranean hundreds of times, an activity they asserted was in keeping with international law and carried out also by navies from the North Atlantic Treaty Organization (NATO).

Advance knowledge
Ben Yehuda evaded questions during a press conference about whether the Navy had advance knowledge that the Francorp was carrying weapons, though local journalists who had been briefed on the matter by officers said that the ship had been under surveillance for two days.

The military said it estimated that there were 3,000 rockets aboard the ship, enough for about one month's worth of fighting against Israel. Analysts say that Iran wants to use the threat of an attack from Hezbollah to deter an Israeli strike on its nuclear facilities.

"It's a victory for Israeli intelligence. It's very unlikely this was by pure chance,'" says Meir Javedanfar, an Iran expert based in Tel Aviv. "It also shows that Iran is preparing itself for a showdown in Lebanon, be it before or after, a possible Israeli strike. It shows that despite the recent setbacks for Iran, the regime still continues to arm its allies."

The weapons seizure was reminiscent of the Navy's 2002 seizure of the Karine A - also far from the Israeli shore -- which was ferrying some 50 tons of arms from Iran to Palestinian militants loyal to Yasser Arafat at the height of the uprising against Israel.

Earlier this year, Israeli planes reportedly destroyed a 23-truck weapons convoy in Sudan that Israel said was bound for Hamas in Gaza. Cyprus detained and investigated a Russian ship under a Cypriot flag with a weapons shipment from Iran to Syria.

Israel also accuses Iran of supplying Hamas militants in Gaza with rockets and anti-tank missiles. On Tuesday, military intelligence chief, Maj. Gen. Amos Yadlin told a parliament committee that Hamas had test-fired a rocket capable of reaching the southern suburbs of Tel Aviv. Hamas later on Tuesday denied the allegation.

Intelligence officials have said that Hamas has nearly reached its pre-war rocket strength thanks to smuggling tunnels.

In an interview with Israel Radio on Wednesday, Knesset Member Shaul Mofaz, a former chief of staff, said the relative quiet along Israel's border was misleading.