The United States said Tuesday it had busted a plot conceived at high levels of Iran's revolutionary leadership to kill the Saudi envoy to Washington in a major terror attack, and vowed to hold Tehran to account.

An aide to Iran's President Mahmoud Ahmadinejad later on denied allegations that the Islamic republic was involved in such plot.

Israeli and Hamas officials announced late Tuesday that they have reached a prisoner swap deal to free a captured Israeli soldier held in the Gaza Strip in exhange for hundreds of Palestinian prisoners, capping five years of painful negotiations that have repeatedly collapsed in fingerpointing and violence.

The deal would bring home Sgt. Gilad Schalit, who was captured in a cross-border raid in June 2006 by Palestinian militants who burrowed into Israel and dragged him into Gaza. Little has been known about his fate since then.

Egyptian Deputy Prime Minister Hazem al-Beblawi resigned on Tuesday following deadly clashes in the capital that left 25 people dead, the official MENA news agency reported.

Beblawi -- one of two deputy prime ministers who also has the finance portfolio -- said he tendered his resignation after Sunday's deadly clashes "which shook the security of the society, which is the government's responsibility" to ensure.

Libya's new regime fighters Tuesday seized the police headquarters in the center of Moammar Gadhafi's hometown Sirte after the toppled leader's diehards deserted it, an Agence France Presse reporter said.

The National Transitional Council combatants celebrated the takeover of the strategic security building by honking the horns of their vehicles and firing into the air.

Kuwait's foreign minister told reporters Tuesday the Arab world's foreign ministers are to meet to discuss developments in Syria.

"There will be a meeting of Arab foreign ministers to study the events in Syria," Sheikh Mohammed al-Sabah told a news conference in Kuwait's capital, without specifying the date for the gathering.

Israeli forces on Tuesday demolished for the third time a mosque in a remote Bedouin village in the Jordan valley, Palestinian security forces said.

The demolition took place in the village of Khirbet Yarza, some five kilometers east of Tubas in the northeastern corner of the West Bank.

Tens of thousands of Yemenis marched on the streets of the capital Tuesday, demanding for a second straight day the U.N. Security Council take action against President Ali Abdullah Saleh.

"This is a message to the world, to the powerful nations, and to the Security Council...take Saleh and his regime to court," the protesters chanted from Sanaa's Change Square.

A Yemeni journalist detained last week by dissident General Ali Mohsen al-Ahmar said Tuesday that he had been freed.

Mohammed Sudam, a Reuters reporter who also works as an interpreter for President Ali Abdullah Saleh, was detained Friday night at a checkpoint manned by Ahmar's troops on the way home from the airport after a trip to Cairo.

China urged Syria Tuesday to move faster to implement reforms, a week after Beijing infuriated the West by blocking a U.N. resolution against President Bashar Assad's deadly crackdown on protests.

It is the first time that China has veered away from its longstanding policy of non-interference in the affairs of Syria, which has been rocked by anti-government protests and violence since earlier this year.

Israeli activists on Tuesday prevented Palestinians from visiting relatives held in a jail in northern Israel to protest the ongoing captivity of soldier Gilad Shalit, an activist told Agence France Presse.

Around 50 supporters of Shalit, who was snatched by Gaza militants in 2006, stopped a bus carrying Palestinians from reaching the Gilboa Prison in the Beit She'an valley, Shalit activist Shimshon Liebman said.