Islamic extremists from Western countries who have gone to fight in Syria could carry out terrorist attacks when they return home, British Foreign Secretary William Hague warned on Thursday.

Hague said war-torn Syria had become the "number one destination" for jihadists from around the world.

U.S. Secretary of State John Kerry said Thursday the death toll in Syria may have reached 90,000, citing figures given to him by his Saudi counterpart Prince Saud al-Faisal.

"I had occasion ... to speak this morning with the foreign minister of Saudi Arabia. The first thing he mentioned to me was in his estimate perhaps as many as 90,000 people who have been killed in Syria," Kerry told reporters.

An Israeli court on Thursday found two senior Hamas members who had taken refugee in Red Cross east Jerusalem offices guilty of "membership of a terror organization" and staying in Israel without permits.

Former Palestinian minister for Jerusalem affairs Khaled Abu Arafeh and Hamas MP Mohammed Totah had barricaded themselves in the International Committee of the Red Cross offices on July 1, 2010, but were arrested on January 23, 2012.

The Gulf monarchies on Thursday rejected as a provocation an Iranian proposal to include the Syria crisis and the situation in Bahrain on the agenda of upcoming talks on Tehran's nuclear program.

The head of the Gulf Cooperation Council (GCC), Abdellatif Zayani, announced the "total rejection" of the Iranian proposition, calling it "a provocation" and "interference in the internal affairs of Arab states."

A new peace plan for Syria, involving the creation of a senate to oversee a power transition, is currently making the rounds in the United Nations, Saudi newspaper Asharq al-Awsat reported.

The daily reported that it had obtained a copy of the plan aimed at ending Syria's 23-month conflict, saying that it had been drafted "under U.N. supervision".

Saudi Arabia's King Abdullah on Thursday appointed Prince Khaled bin Bandar bin Abdul Aziz as the new governor of the capital Riyadh, the official SPA news agency reported.

It said the king also named one of his sons, Prince Turki, as deputy governor in place of Prince Mohammed bin Saad, who had asked to step down.

Aid delivery is in jeopardy for an estimated 100,000 people affected by violence in Sudan's Darfur region unless authorities grant better access, the United Nations warned on Thursday.

One humanitarian agency has said the number of displaced people is the largest in recent years in Darfur, where a decade of civil war has been compounded by inter-Arab violence, banditry and tribal fighting.

Israeli army gunfire wounded two Palestinians near northern Gaza's border with the Jewish state on Thursday, an official with the Hamas government said.

Gaza's health ministry spokesman Ashraf al-Qudra said one was in serious condition after being hit in the chest, while the other was in moderate condition. The incident occurred east of the town of Beit Hanun.

A teenager was shot dead near Bahrain's capital on Thursday as clashes erupted when hundreds took to the streets to mark the second anniversary of a Shiite-led uprising against the kingdom's Sunni rulers.

The demonstrations, staged early morning in Shiite-populated villages across the Gulf archipelago, turned violent when police fired shotguns and tear gas to disperse the crowds, wounding several people, witnesses said.

Syrian rebels from the Islamist al-Nusra Front on Thursday seized the town of Shadadeh in the oil-rich northeastern province of Hasake, on the border with Iraq, a monitoring group said.

"After three days of fierce battles against the army, al-Nusra Front fighters have seized control of Shadadeh," said the Syrian Observatory for Human Rights, which relies on a network of activists, doctors and lawyers for its reporting.