The United States fears a Hezbollah attack during its evacuation of up to 5,000 Americans from war-torn Beirut, and is working with Israel to coordinate their safety, the U.S. military said Tuesday.

Vice Admiral Patrick Walsh said Israel was aware that the U.S. would be ferrying evacuees from the port of Beirut to Cyprus on the chartered cruise ship Orient Queen, and that several U.S. and Israeli warships would be on hand to protect Americans from an attack by the guerrilla group.

"I’m concerned about attacks on ships. We do not assume anything. And that sort of scenario is something we are planning for," Walsh said to reporters Tuesday.

He said the U.S. was working with Israel through the European Command segment of the military.

President Bush, meanwhile, told reporters late Tuesday that he suspects Syria is trying to reassert influence in Lebanon more than a year after Damascus ended a long-term military occupation of its smaller, weaker neighbor.

"It's in our interest for Syria to stay out of Lebanon and for this government to survive," Bush said in a reference to the Lebanese government. The president also said he believed the Syrian-backed guerrilla group Hezbollah is the "root cause" of the current conflict. (Full coverage)

At least 320 Americans were evacuated from Lebanon to Cyprus by the end of Tuesday and 1,000 more will leave the following day after the Greek cruise ship was expected to collect at least 750 Americans.

The State Department said 5,000 Americans trapped in the war-torn region of Lebanon had requested to be evacuated and a fleet of vehicles was en route to the area to ship them out.

The Orient Queen left the Mediterranean island of Cyprus for Beirut to join several U.S. military helicopters already ferrying dozens of Americans out of southern Lebanon.

“The threat level allows us to move ferries back and forth but it's not something we take for granted. We'll also have warships in position to ensure the safe passage of citizens from Lebanon to Cyprus,” Walsh said. (Full coverage)

Rockets Target Northern Israel

One Israeli was killed and several others wounded in a new barrage of rockets fired across the border by Hezbollah after Israeli warplanes struck an army base outside Beirut Tuesday, casting a shadow over diplomatic efforts aimed at stemming the violence.

The Israeli attack on a Lebanese army base in Kfar Chima, left 11 soldiers dead and 35 wounded, the Lebanese military said. The base is in an area next to Hezbollah targets in southern Beirut that have been frequently hit by Israeli warplanes in recent days.

Israel gave no indication why the base was hit, but Lebanese media suggested Israel may be trying to prevent the quick repair of previously destroyed bridges and roads.

At least five people also were killed when an Israeli bomb hit a house in the village of Aitaroun, near the border with Israel, witnesses said. Israeli warplanes also fired four missiles on the eastern city of Baalbek, wounding four, and southern Beirut, both thought to be Hezbollah strongholds. Plumes of black smoke rose over the capital's southern suburbs.

Israeli planes also attacked four trucks, part of a new tactic of targeting trucks suspected of carrying Hezbollah missiles.

The Islamic militant group fired rockets that knocked down a three-story house in northern Israel and later killed one Israeli and wounded several others in the town of Nahariya, Israeli officials said.

Rockets also struck Haifa, Israel's third-largest city, for the third day in a row, falling near the port and a railway depot, but no casualties were immediately reported. Eight people were killed in an attack on Haifa on Sunday. (Full coverage)

Offensive Could Last Several More Weeks, Israeli Prime Minister Says

Israeli officials said their military offensive in Lebanon could last several more weeks and possibly involve large numbers of ground forces — casting doubt on the effectiveness of growing diplomatic efforts to broker a cease-fire.

Prime Minister Ehud Olmert told a visiting U.N. delegation that "Israel will continue to combat Hezbollah and will continue to strike targets of the group" until captured soldiers are released and Israeli citizens are safe from attacks. (Full story)

Iran: No Place in Israel is Safe

Heightening fears that the current battle could extend beyond Lebanon and Israel's borders, Iran's parliamentary speaker warned that no part of Israel is safe in the current fighting with Lebanon, referring to the range of guerrilla rockets.

Speaking to a crowd of thousands of anti-Israel demonstrators in Palestine Square, Tehran, Speaker Gholam Ali Haddad Adel told Israelis: "The towns you have built in northern Palestine (Israel) are within the range of the brave Lebanese children. No part of Israel will be safe." (Full story)

Egypt Opens Border for Palestinians to Pass

Thousands of Palestinians, some fainting in the midday heat, flooded to the border checkpoint with Gaza Tuesday when Egypt and Israel reopened it for the first time in three weeks.

Most Palestinians were returning to Gaza, and many said they had run out of money and been exhausted by the weeks-long wait on the Egyptian side of the border. (Full story)

U.S. Congress is considering resolutions supporting Israel.

United Nations evacuates all non-essential personnel from Lebanon.

U.N. Security Council awaits return of U.N. mission to the region.

Iran says a cease-fire and prisoner swap would be a fair trade.

• A brief history of the Lebanese-Israeli conflict.

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CountryWatch: Israel | Lebanon | Syria | Iran

FOX News' James Rosen and the Associated Press contributed to this report.