Three prominent Egyptian secular activists went on trial on Sunday charged with participating in a violent protest, following a restrictive new law that has sparked international criticism.

The trial of Ahmed Maher, Ahmed Douma and Mohammed Adel is the first of secular activists since Islamist president Mohammed Morsi was deposed by the army in July. Adel is being tried in absentia.

Two Yemeni officers were killed Sunday in separate attacks targeting members of the security forces across the country, a security official and the defense ministry news website said.

In the first attack, unknown gunmen traveling in a car shot dead the security chief of a presidential palace in Yemen's second-largest city Taez, the official said.

One person was killed and five wounded Sunday when a car blew up in a cemetery in Libya's increasingly volatile second city Benghazi, security and medical sources said.

The explosion, after the funeral of a police officer killed in a similar blast, killed one of the car's passengers, security spokesman Ibrahim al-Sharaa said.

An Egyptian court was to try 21 Islamist university students Sunday, including a Turkish man, after a violent protest outside the prestigious al-Azhar religious institution, prosecution officials said.

The students at al-Azhar University in Cairo are accused of attacking the headquarters of the Sunni Muslim authority in a November protest.

Gulf Cooperation Council states must be part of the negotiations between major world powers and Iran, oil-rich Saudi Arabia's former intelligence chief said on Sunday.

Iran and major powers broke through a decade of gridlock on November 24 to agree an interim deal that would freeze parts of Iran's controversial nuclear program while easing some of the crippling international sanctions against it.

Syrian regime forces made gains Sunday in the key town of Nabuk, one of the last rebel-held areas in the Qalamoun region bordering Lebanon, a watchdog said.

"There is fierce fighting in Nabuk between government forces, backed by Hizbullah fighters, and al-Nusra Front and the Islamic State of Iraq and the Levant," the Syrian Observatory for Human Rights said.

Yemen LNG gas company has evacuated hundreds of workers from its Balhaf terminal on the Gulf of Aden, after a mortar round hit the site, an oil ministry official and employees said Sunday.

Company staff, including foreigners, were evacuated to the capital on four planes as a precaution over fears of potential attacks on the terminal, employees said.

Israeli President Shimon Peres said Sunday he would be prepared to meet his Iranian counterpart Hassan Rouhani, even though their two countries consider each other arch-enemies.

Asked at an economic forum over a possible meeting, Peres replied: "Why not? I don't have enemies. It's not a question of personalities but of policies.

A visit to Israel by Dutch Prime Minister Mark Rutte Sunday was marred by a dispute over a new security scanner on the Gaza border, an Israeli official said.

Rutte was to have inaugurated the scanner on the frontier with the Palestinian Islamist-ruled enclave, but the ceremony was put off because of the row.

A wave of bombings mostly targeting Shiite areas in and around Baghdad killed at least 35 people Sunday as surging violence spurs concerns Iraq is falling back into all-out conflict.

The blasts, including seven car bombs, are the latest in a months-long rise in bloodshed that has forced the authorities to appeal for international help just months before the country's first elections in four years.