JERUSALEM (AP) -- Israeli naval forces on Wednesday seized a ship laden with rockets allegedly bound for militants in the Gaza Strip, and officials accused Iran of orchestrating the delivery in an elaborate 5,000-mile (8,000-kilometer) journey that included covert stops across the region.
The Syrian-made M-302 rockets would have put Israel's biggest cities well within range of Gaza, where militants already possess thousands of less powerful rockets. During eight days of fighting in 2012, armed groups fired 1,500 rockets into Israel, including several that reached the outskirts of Jerusalem and Tel Aviv.
The naval raid, which took place in the Red Sea hundreds of miles from Israel, came as Iran showed off powerful new ballistic missiles equipped with multiple warheads. The arms bust drew renewed Israeli calls for world powers to toughen their stand in negotiations over the Iranian nuclear program.
"Iran has been exposed for what it is. It smiles in the Geneva talks about its own nuclear ambitions, gives soothing words, and as they're doing that, they're shipping these deadly weapons to the world's worst terrorists," Prime Minister Benjamin Netanyahu said in California during a U.S. visit. "Such a regime must not be able to have the capacity to make nuclear weapons."
Israel believes that Iran is trying to build a nuclear weapon, a charge Iran denies. Israel says a nuclear-armed Iran would pose a threat to the existence of the Jewish state, citing Iranian calls for Israel's destruction, its development of long-range missiles and its support for hostile militant groups.
Netanyahu has been an outspoken critic of the efforts by six world powers to negotiate a deal with Iran that would substantially scale back its nuclear program in exchange for ending international sanctions. He says a current, interim deal gives Iran too much relief while getting little in return, and fears a final agreement would leave Iran with the capability to make a bomb.
Since the global powers reached their interim deal with Iran last November, Netanyahu's warnings about Iran have been largely ignored by world leaders.
Iran's announcement Wednesday that it now has missiles with multiple warheads, greatly boosting their destructive power, only heightened Israeli concerns. The semiofficial Fars news agency said the new Qiam missile was specifically built to target U.S. bases in the region. Iran already possesses missiles capable of striking Israel and parts of Europe.
Israeli officials said that Wednesday's naval raid took place in international waters about 100 miles (160 kilometers) off the coast of Sudan, and came after months of painstaking intelligence work.
They said the rockets had been flown from Syria to Iran months ago, then shipped from Iran's Bandar Abbas port to Umm Qasr, Iraq, before being loaded onto the KLOS C civilian ship destined for Sudan. From there, Israeli officials said they were to be smuggled overland through Egypt to Gaza -- a route that has been used in the past.
"We have been following this shipment for a long time through impressive intelligence work," Israel's military chief, Lt. Gen. Benny Gantz, told reporters. He did not elaborate, but Israel is believed to use satellites and on-the-ground spies to collect information on its enemies.
Rear Adm. Yaron Levy, the navy's chief of operations, said the long distance from Israel, about 900 miles (1,500 kilometers) away, and the presence of foreign navies and merchant ships, complicated the mission and made it difficult to protect secrecy. He said Israel deployed a "strong naval force" but halted the Panamanian-flagged ship without incident.
"We got on the ship with the captain's permission. We found what we found, and you know the rest of the story," he said.
Defense Minister Moshe Yaalon said the circuitous route, stretching nearly 5,200 miles, or 8,300 kilometers, was meant to conceal the shipment.
"It was an Iranian attempt to bring weapons to the Gaza Strip without leaving Iranian fingerprints," he said. "Apparently they tried to conduct a secret operation that we managed to thwart."
In Washington, State Department spokeswoman Jen Psaki said the U.S. had been in close coordination with Israel throughout the mission.
"Even as we continue our efforts to resolve our concerns over Iran's nuclear program through diplomacy, we will continue to stand up to Iran's support for destabilizing activities in the region, in coordination with our partners and allies," she said.
The ship was far out at sea Wednesday and was being brought to Israel. It was expected to arrive in the Israeli port of Eilat in the coming days. Video released by the military showed Israeli soldiers on the ship inspecting the rockets, shipped in large crates. The video also showed beige bags containing cement with the words "Made in I.R. Iran," in English, written on them.