Former Egyptian prime minister and presidential hopeful Ahmed Shafiq was forced to flee a campaign rally after protesters threw chairs at him and demanded he leave the area, according to reports on Friday.

Shafiq, who has announced he was running for the top job, was addressing a rally in the impoverished Cairo neighborhood of Imbaba on Thursday evening when some residents began chanting for him to leave.

The Damascus-based chief of Hamas was instrumental in getting Syria to accept an Arab observer mission into the country, the head of the Arab League said on Friday.

Nabil al-Arabi was speaking in Cairo after talks with Khaled Meshaal, the exiled head of the Palestinian Islamist group Hamas.

The United States condemned Friday's deadly suicide bombing which left at least 26 people dead in Damascus, the capital of violence-wracked Syria.

"We categorically condemn this attack," State Department spokeswoman Victoria Nuland told reporters.

Syrian activists on Friday took to the streets across the country in a bid to "internationalize" their cause after the rebel Free Syrian Army urged the Arab League to admit its observer mission is a failure and to turn to the United Nations.

But there has been no let-up in security force fire against demonstrators, with at least 35 people shot dead on Friday, according to the Local Coordination Committees, the main activist group spurring protests on the ground.

The Arab League mission sent to monitor unrest in Syria is unable to do its job properly, French Foreign Minister Alain Juppe said Friday.

"We support the Arab League which has sent observers to Syria but this mission is not at present able to do its job properly," Juppe said on the second day of a visit to Tunisia.

A Fatah delegation was on Friday prevented from entering the Hamas-controlled Gaza Strip where they were to have held reconciliation talks with the Islamist movement, Fatah said.

The planned visit comes as Nabil Shaath, a member of Palestinian President Mahmoud Abbas' Fatah party's central committee, has been in Gaza since January 2 for talks with Hamas leaders and other Palestinian representatives on implementing a reconciliation deal.

A suicide bombing hit Damascus on Friday, killing 25 and wounding dozens of mostly civilians, state media said, blaming "terrorists" for the second such attack on the Syrian capital in two weeks.

But Syria's opposition Muslim Brotherhood called for an international and Arab probe into the bombing, saying it was an act benefitting the regime.

Rockets were fired against Baghdad's Green Zone as Iraq's military marked its anniversary with a parade Friday, a day after the country suffered its worst attacks since August and weeks after U.S. troops left.

In Baghdad, insurgents fired three rockets against the heavily-fortified Green Zone as Prime Minister Nouri al-Maliki presided over a huge military parade to mark the 91st anniversary of the founding of Iraq's armed forces.

U.N. human rights experts may train Arab League observers monitoring the Syrian government's deadly crackdown on opposition protests, a U.N. spokesman said Thursday.

The announcement came the day after Qatar's prime minister sought help from U.N. secretary general Ban Ki-moon, saying the Arab League mission in Syria had made "some mistakes".

Attacks against Shiite pilgrims in Baghdad on Friday killed two people, a day after Iraq suffered its worst violence in five months as it grappled with a political row that has stoked sectarian tensions.

The two bombs exploded in the morning on separate bridges in the Dura neighborhood of south Baghdad, an interior ministry official and a doctor at Yarmuk hospital said.