Syria warned on Sunday that its forces will respond to "intensified" rebel attacks, even as U.N. military observers were headed for the unrest-hit country to monitor a shaky ceasefire.

"Armed terrorist groups have intensified their attacks in a hysterical way against the army, law enforcement forces, and civilians, in conjunction with the approval of the U.N. Security Council resolution to send monitors to Syria," a military official said, quoted by state television.

Arab foreign ministers of the Gulf are to hold a special meeting in the Qatari capital on Tuesday to discuss the islands dispute between Iran and the United Arab Emirates, an official source said.

A Gulf Cooperation Council official said earlier that the meeting would take place in Riyadh but the GCC finally said it will be held in Doha.

Prime Minister Nuri al-Maliki said Iraq's policy of non-interference in Syria and opposition to arming either side is in the country's best interest, in an interview with Kurdish newspaper Awena.

Thousands of people have been killed in a crackdown by President Bashar Assad's regime on a 13-month uprising against his rule but Iraq has strongly opposed proposals from Gulf states, including Qatar and Saudi Arabia, to arm rebel fighters.

Gunmen attacked a police checkpoint in Egypt's Sinai Peninsula on Sunday, killing two officers and wounding another, a security official told Agence France Presse.

The gunmen opened fire on the checkpoint near the town of al-Arish, instantly killing policemen Mohammed Fawzi and Mohammed Mosleh, both 21.

Unknown attackers blew up a house north of the Iraqi capital Sunday, killing three members of a family including a five-year-old boy and also wounding a two-year-old girl, an interior ministry official said.

"Unknown gunmen planted three bombs around a house made of mud and reeds in the Taji area, causing it to completely collapse and killing a father, mother and a five-year-old boy," the official said.

Syrian forces killed four civilians on Sunday in shelling of rebel areas and clashed with gunmen, testing a shaky U.N.-backed ceasefire as international monitors prepared to arrive in the unrest-hit country.

Forces loyal to President Bashar Assad subjected the Khaldiyeh and Bayada neighborhoods of the flashpoint central city of Homs to their fiercest bombardment since the truce came into force at dawn on Thursday, monitors said.

Israel deployed hundreds of police Sunday at its main airport to detain activists flying in to protest the country's occupation of Palestinian areas, defying vigorous Israeli government efforts to block their arrival.

Police spokesman Micky Rosenfeld said hundreds of protesters were expected to land at Ben-Gurion International Airport in the course of the day. The police contingent at the airport was reinforced to deal with possible unrest or disruptions, he said.

An air strike in southern Yemen has killed at least three suspected al-Qaida militants, the defense ministry said in a statement on Sunday.

A security official said the raid late on Saturday was conducted by a U.S. drone against a moving vehicle carrying al-Qaida operatives in the province of Bayda, some 210 kilometers (130 miles) southeast of the capital Sanaa.

Egypt's election commission said on Saturday that ex-spy chief Omar Suleiman, Muslim Brotherhood candidate Khairat al-Shater and Salafist politician Hazem Abu Ismail are among 10 candidates barred from running for president.

Commission official Tarek Abul Atta told AFP that Suleiman had been disqualified because he failed to get endorsements from 15 provinces as per law.

Saudi Arabia on Saturday denied any deal with Sweden to build an arms factory, in its first reaction to a weeks-old controversy which led to the resignation of the Swedish defense minister.

"The Saudi Defense Ministry affirms that no accord has been signed in the past with the friendly kingdom of Sweden to build a weapons factory in Saudi Arabia and that no such project exists," state news agency SPA reported.