U.S. Secretary of State Hillary Clinton on Tuesday vowed to press ahead with support for democracy promotion groups, saying that they play a critical role despite a crackdown in Egypt.

Clinton, addressing U.S. ambassadors from around the world who are back in Washington for a group conference, said that civil society groups are vital to encouraging U.S. goals such as advancing democracy and women's participation.

Arab League chief Nabil al-Arabi on Tuesday called for an international probe into "crimes" committed against civilians in Syria, particularly in the flashpoint provinces of Homs and Idlib.

"Media reports about the horrible pictures concerning crimes committed against innocent civilians in Homs and Idlib and other parts of Syria can be described as crimes against humanity," Arabi said in a statement.

The U.N. human rights office will send observers to Syria's neighboring countries to collect evidence and document atrocities in the strife-torn state, the deputy rights commissioner said Tuesday.

"We will be sending monitors for information collection and documentation of the violations and atrocities in the border areas in the neighboring countries later this week," said Kang Kyung-wha, Deputy High Commissioner for Human Rights.

Syria's embattled President Bashar al-Assad issued a decree on Tuesday setting May 7 as the date for parliamentary elections that were delayed last year, the state news agency SANA reported.

The vote is part of a raft of reforms announced by Assad in a bid to calm a year-long uprising against his regime that began with democracy protests.

Baghdad's international airport will shut from March 26 until the end of an Arab League summit in the Iraqi capital on March 29, the country's civil aviation chief told Agence France Presse on Tuesday.

"We will close off flights from the 26th until the end of the summit," said Nasser Hussein Bandar, head of Iraq's civil aviation authority. "It (the airport) will be used for receiving delegations."

Russia said Tuesday it will press Syria to accept international monitors who could observe the implementation of a "simultaneous" ceasefire between government troops and rebels.

Foreign Minister Sergei Lavrov said Russia was discussing the proposal with both the Arab League countries and at the United Nations, where the Security Council debated the crisis on Monday.

Syria has planted landmines near its borders with Lebanon and Turkey, along routes used by refugees fleeing the strife-torn country, Human Rights Watch (HRW) charged on Tuesday.

"The Syrian regime is trying to prevent people from going in and from fleeing the country," said Nadim Houry, deputy director of the group's Middle East and North Africa division.

Five al-Qaida militants were killed in an air strike on their car in Yemen's Bayda province on Tuesday, a security official said, after unrest there earlier in the day left five people dead.

"A fighter jet raided a car carrying five al-Qaida militants," said the official. "All five were killed." A tribal chief confirmed the raid.

Saudi Arabia on Tuesday executed a Saudi who killed a man in a tribal feud as well as a Syrian drug smuggler, the ministry of interior announced.

"Humam Eid al-Kindar, a Syrian, was arrested for smuggling 169,000 banned pills," state news agency SPA quoted a ministry statement as saying.

An Algerian court sentenced the head of al-Qaida's north African offshoot to death in his absence Tuesday for a string of 2007 attacks, including the deadly bombing of the prime minister's office.

Abdelmalek Droukdel, leader of al-Qaida in the Islamic Magreb (AQIM), and eight co-defendants were sentenced to death for premeditated murder, membership of a terrorist group and attacks using explosives, said judge Tayeb Hillali of the court in Algiers.