Syria was hit by the third lethal car bombing of the weekend on Sunday as U.N. teams readied for a government-led humanitarian mission and to work to launch a monitoring operation to end a year of bloodshed.

The Syrian Observatory for Human Rights, in a statement, said the latest blast targeted political security offices in the northern city of Aleppo, killing three civilians and wounding more than 25 others.

Syrian security forces mounted operations on Sunday in the northern province of Aleppo, northwestern Idlib, the east's Deir Ezzor region, Daraa in the south and al-Raqqa in the northeast, killing at least 37 people across the country, activists said.

Five rebels from the Free Syrian Army and three children were among the 37 casualties, the Local Coordination Committees, the main activist group spurring protests on the ground, said.

Some 200 Syrians fled to Turkey on Saturday, bringing to nearly 16,000 the number who have crossed the border to escape an ongoing government crackdown, Turkish Anatolia news agency said Sunday.

The refugees, including women and children, crossed into Hatay province from Syria's northwest Idlib province, where government troops have launched a crackdown on rebels.

Thousands of grieving Coptic Christians packed St Mark's Cathedral in Cairo on Sunday to bid farewell to Pope Shenuda III, his body on a wooden throne, as the church considered a new head of the anxious community.

Shenuda died on Saturday aged 88 after a long illness, setting in motion the process to elect a new patriarch for the Middle East's largest Christian community.

Missiles fired from the sea slammed into Al-Qaida positions in the southern Yemeni city of Zinjibar on Sunday killing at least 16 suspected militants, a local official said.

He said the heavy shelling began overnight targeting the northeastern suburbs of Zinjibar, which jihadists have controlled since May following fierce fighting with government troops.

Syria said Sunday that two deadly bomb blasts in Damascus were aimed at sabotaging peace efforts, as U.N. experts prepared to join a government-led humanitarian mission to devastated protest hubs.

"Yesterday's explosions were carried out by terrorists supported by foreign powers which finance and arm them," charged Al-Baath newspaper, mouthpiece of Syria's ruling party of the same name.

Israel's intelligence service Mossad agrees with U.S. assessments of Iran's nuclear ambitions, even though Israeli leaders have talked about Tehran's plans to acquire nuclear weapons, The New York Times reported late Saturday.

"Their people ask very hard questions, but Mossad does not disagree with the U.S. on the weapons program," the newspaper quoted an unnamed former senior U.S. intelligence official as saying.

Israeli troops wounded a six-year-old Palestinian boy on Sunday when they opened fire east of the town of Rafah, in southern Gaza, Palestinian medical sources said.

"A six-year-old Palestinian child was wounded by Israeli army gunfire near the Kerem Shalom crossing, east of Rafah, in the southern Gaza Strip, which is where the family lives," emergency services spokesman Adham Abu Selmiya told AFP.

Two "terrorists" were killed as a booby-trapped car they were driving blew up in a Palestinian refugee camp in a suburb of Damascus, Syria's state news agency SANA reported on Sunday.

It said the blast in Yarmouk camp on Saturday, the same day as authorities said 27 people were killed in two suspected car bombings in central Damascus, also damaged parked cars and shattered windows of nearby buildings.

Two gunmen shot dead on Sunday a U.S. citizen who worked at a language school in Yemen's second city of Taez, a security official said.

The assailants rode a motorbike in their attack on the man, who was the deputy director of a Swedish language center in the city, 270 kilometers (173 miles) southwest of Sanaa, the official said on condition of anonymity, adding they fled the scene after the shooting.