Israel claims its naval commandos have intercepted a freighter carrying arms, apparently from Syria, bound for Iranian-backed Palestinian militants in the Hamas-controlled Gaza Strip.

The Israelis swooped in the eastern Mediterranean amid spreading political upheaval across the Arab world that they say Iran, Syria's ally and Israel's key enemy, is exploiting to undermine the Jewish state.

The Israeli military said the German-owned Victoria, registered in Liberia, sailed from the Syrian port of Latakia and was en route to Alexandria, Egypt, when it was boarded in international waters 200 miles off the Israeli coast.

The locations listed by the Israelis are significant. Earlier this month, two Iranian navy vessels, the frigate Alvand and the supply ship Kharq, transited the Suez Canal from the Red Sea into the Mediterranean. They were the first Iranian warships to do so since Iran's Islamic Revolution in 1979 that toppled the pro-Western Shah Mohammad Reza Pahlavi, an ally of Israel.

The two vessels sailed to Latakia, supposedly on a goodwill visit by the Iranian navy to the Islamic Republic's key Arab ally. The Iranians said the controversial visit had been arranged long before the upheaval in the Arab world erupted in Tunisia in early January.

But Israel viewed the vessels' transit through the Suez Canal only days after Egyptian President Hosni Mubarak had been forced to step down, as a provocation.

Under Mubarak, Egypt was virulently anti-Iranian and was committed to the landmark peace treaty his predecessor, Anwar Sadat, had signed with Israel in March 1979, a scant two months after the fall of the shah's regime.

There are concerns in Israel, not to mention the United States, that whatever regime emerges in Egypt will be less dedicated to the peace treaty, which polls indicate is widely reviled by a majority of Egypt's 80 million people, and less hostile toward Iran.

"With the fall of the Mubarak regime, which maintained a close relationship with Israel for over 30 years, and the political transformation sweeping across the Arab world, the Islamic Republic has found new opportunities to reassert its regional influence, and the first ostensible shift in relations appears to be between Egypt and Iran," observed analyst Nima Adelkhah of the Jamestown Foundation, a Washington think tank.

Egypt's Defense Ministry said it couldn't prevent the Iranians using the canal because the two countries weren't at war.

Adelkhah noted that Cairo's "army-led government … appears to shy away from any conflict that could arise from the passage of Iranian warships. For the most part, Iran knows Egypt's vulnerability and has exploited the situation with the navy's Suez passage."

It's not known whether there's a direct link between the Iranian ships' visit to Latakia and the alleged loading of Gaza-bound arms at that port by the Victoria.

But the Israelis have intercepted several ships carrying weapons supposedly headed for Gaza or the Hezbollah militants in Lebanon, Iran's main proxy in the Levant, in the last few years.

Amid the prevailing uncertainty, the Israelis have already started to redeploy troops to the Jewish state's border with Egypt's Sinai Peninsula. That desert frontier has been unmanned since the early 1980s following the 1979 peace pact.

The Israelis worry that Mubarak's containment of Hamas in the turbulent Gaza Strip, to prevent its Islamic militants igniting trouble in Egypt, may also be coming to an end now that he has lost power. That makes Israeli sensitivity about arms shipments to Hamas in Gaza even more acute.

Last week, a senior Israeli commander said Tehran and Hezbollah have provided Hamas with a "vast amount" of anti-tank and anti-aircraft missiles as well as rockets able to hit Israeli cities and key military installations since Israel's 22-day invasion of the Gaza Strip in the winter of 2008-09.

Some 500 Hamas activists were killed in Operation Cast Lead, along with some 1,000 civilians, which drew intense international criticism.

Hamas has made no secret that it has rearmed and rebuilt its forces since then. Israel claims hundreds of Hamas cadre have undergone military training in Iran.

Israeli Deputy Foreign Minister Danny Ayalon alleges that arms smuggling into Israeli-blockaded Gaza from Egypt through underground tunnels has increased during the upheaval in Egypt and the wider Arab world.