The Israeli military on Wednesday released documents and photos it said proved Iran was behind a huge shipment of weapons Israeli navy commandos intercepted last week.

Israel has said the cargo ship its troops seized off the coast of Cyprus was carrying 500 tons of Iranian-made weapons for Lebanese Hezbollah militants. The ship had dozens of containers with Iranian markings on it.

On Wednesday, the military released what it said was the ship's manifest that showed it was handled by "Islamic Republic of Iran's Shipping Lines." It also produced labeling from the containers indicating the ship originated in Isfahan, Iran, and a customs form stamped by the Iranian armed forces.

Both Iran and Hezbollah have denied the Israeli claims. Officials at Iran's Foreign Ministry were not immediately available for comment Wednesday.

An international expert who examined the documents and pictures of the weapons said the arms came from Iran, but it was not possible to determine whether the Iranian government was directly involved. Another was not prepared to pinpoint the source of the weapons.

On Tuesday, the United States accused Iran of violating a U.N. arms embargo by secretly sending the weapons aboard the "Francop" — a merchant ship flying the flag of Antigua and destined for the Syrian port of Latakia.

Israel has showcased the haul as proof of its long-standing contention that Iran is supplying large quantities of arms to Hezbollah and Hamas militants in Gaza.

Israel says the confiscated arms cache — the largest it has ever seized — did not include any new types of weapons for Hezbollah. However, the arms would have given Hezbollah a month's worth of firepower in time of war. Israel has urged the world to focus on the threat from the Lebanese militants' chief backer — Iran.

Among the arms Israel says it found aboard the vessel were 9,000 mortar bombs, 3,000 Katyusha rockets, 3,000 anti-tank shells, 20,000 grenades and more than a half million rounds of small arms ammunition.

Israel also says that a close examination of the munitions themselves conclusively point to Iran as the source of the shipment.

The containers were stuffed with sacks of polyethylene pellets used to conceal the munitions, Israel said. According to the markings, the polyethylene was produced by Iran's National Petrochemical Co. It included a telephone number that begins with 98 — which is Iran's international dialing code.

Also discovered were thousands of rounds of mortar bombs and artillery rockets manufactured by the Iranian defense industry, such as 107 mm "Haseb" artillery rockets that are identical to those used by Iranian-armed Iraqi insurgents.

Israel also said it found a large number of AZ111-A2 fuses, which, according to Jane's Ammunition Handbook, is Iranian ordnance developed specifically to meet its military requirements.

The Associated Press showed the documents and pictures of the weapons supplied by Israel to two independent arms experts for their assessment.

The pictures included markings in English on a 107mm rocket with "IRISL" letters stenciled on the sides of containers — which the Israelis said stands for "Islamic Republic of Iran Shipping Lines." There were also pictures of boxes labeled "Ministry of Sepah," which Israel said signified the Iranian military, and cases of AZ111-A2 fuses the Israelis said were made in Iran.

"Sepah" is a term that sometimes refers to the Iranian Revolutionary Guards. A reference to an Iranian "Ministry of Sepah" is found in a February 2008 document composed by the International Agency for Atomic Energy.

Defense expert James Lewis at the Washington-based Center for Strategic and International Studies said the arms Israel captured "were indeed Iranian," but it couldn't be determined whether the Iranian government had ordered the shipment.

He said Iran's Revolutionary Guard could have acted on its own or that even a rogue element in Iran could have orchestrated the shipment. "The number of people who decided to do this are more than one," Lewis said.

The capture of one shipment won't change much, Iranian shipments have "been going on for years and no one has been able to stop it," Lewis said. "Iran will deny it and no one is going to get involved."

Alex Vatanka, IHS Jane's security editor, who also examined the Israeli photographs, said the significance of the Francop capture — if proven Iran was behind it — was its timing, since it comes as Iran faces stepped up pressure over its controversial nuclear program.

"What does that tell us about their threat perception, about their own security priorities?" he said. "It seems to be an indicator of a certain hardline interest in Iran being almost careless about the consequences of their actions."