Turkish Prime Minister Recep Tayyip Erdogan warned on Monday of a "civil war" in neighboring Syria, where President Bashar al-Assad's regime is persisting with a deadly crackdown on opponents.

"The situation that has emerged there is right now heading towards a religious, sectarian and racial civil war. This must be stopped," Erdogan said at a televised press conference.

Iraq's fledgling police force, completely reformed after the 2003 U.S.-led invasion, on Monday marked 90 years since its foundation at a time of raised sectarian tensions due to a political standoff.

The force, which has apologized for acts committed during the rule of now-executed dictator Saddam Hussein, held ceremonies in major cities such as Baghdad and Basra, after the army marked their 91st anniversary with a huge parade in the capital's heavily-fortified Green Zone on Friday.

A pipeline being built by the United Arab Emirates to export oil from east coast terminals, avoiding the Iran-threatened Strait of Hormuz, will be operational by June, its energy minister said Monday.

"The pipeline is almost complete. It will be operational within six months ... by May or June," Mohammed bin Dhaen al-Hameli told reporters.

The opposition Muslim Brotherhood accused the Arab League of seeking to "cover up the crimes" of the Syrian regime, after the pan-Arab organization decided to extend its observer mission.

"It is clear that the observer mission in Syria seeks to cover up the crimes of the Syrian regime by giving it the time and opportunity to kill our people and break their will," Brotherhood spokesman Zuhair Salem said.

Yemen's interim government agreed Sunday to grant President Ali Abdullah Saleh amnesty against prosecution, paving the way for his departure in line with a Gulf plan to end deadly protests against his rule.

The government issued a draft law by which Saleh and his aides "who worked with him in all government, civil and military departments during the years of his rule, are granted amnesty against legal and judicial prosecution," it said in a statement carried by Saba state news agency.

The prime minister in the Hamas-ruled Gaza Strip on Sunday promised "difficult days" for Israel, and at a rally in Tunis urged Arab Spring revolutionaries to fight for an independent Palestine.

Ismail Haniya received an ovation from the crowd of some 5,000 men, women and children gathered in a stadium waving Palestinian, Tunisian and Hamas flags.

Youths in Kasserine, a town at the forefront of Tunisia's uprising a year ago, on Sunday heckled the men their revolution brought to power, radio reports and residents said.

President Moncef Marouzki and Prime Minister Hamadi Jebali, who took office last month, were welcomed to the regional capital by a group of 200 to 300 youths chanting "go home".

Syrian security forces and pro-regime militias on Sunday shot and killed at least 17 civilians as troops and deserters engaged in deadly battles, activists and a human rights group said.

The latest violence came as the Arab League said its controversial observer mission in Syria would continue despite "harassment" by both the government and the opposition.

Arab ministers meeting in Cairo on Sunday gave observers in Syria the green light to continue their mission and called for an "immediate" end to the violence there.

The Arab ministerial committee on Syria "has decided to give Arab League observers the necessary time to continue their mission according to the protocol," which states that the mission is for the duration of one month.

Four Palestinian men were detained on Sunday after Israeli troops at a West Bank checkpoint discovered 12 pipe bombs, a knife and a gun in their possession, an Israeli police spokesman said.

"Four Palestinians were arrested at the Salem checkpoint. They had a commando knife, a pistol and 12 explosives. They were arrested and taken for questioning and the investigation is continuing," spokesman Micky Rosenfeld told Agence France Presse.