Iraq on Thursday executed Saddam Hussein's presidential secretary and chief bodyguard Abid Hamid Mahmoud, justice ministry spokesman Haidar al-Saadi said.

"He was executed today," Saadi said, adding: "The ministry of justice implemented the execution sentence against the criminal Abd Hmoud... for genocide," referring to Mahmoud by the name Iraqis call him.

The Syrian army is preventing U.N. observers from reaching a farmland region where at least 55 people were reportedly killed by militants loyal to President Bashar Assad, activists said Thursday.

Attacks in central Iraq left five security members dead and an alleged al-Qaida fighter killed two prison guards Thursday, amid a recent spike in unrest that has broken a relative calm in Baghdad.

The violence comes just days after a suicide car bomb outside Iraq's Shiite religious foundation's headquarters in Baghdad killed 25 people, and during a protracted political crisis that has raised sectarian tensions.

The international community has to do more to isolate the Syrian regime after the latest "brutal and sickening" massacre in the country, British Prime Minister David Cameron said Thursday.

"We need to do much more to isolate Syria, to isolate the regime, to put the pressure on and to demonstrate that the whole world wants to see a political transition from this illegitimate regime to actually see one that can take care of its people," Cameron told reporters during a quick stop in Oslo.

Syria's Muslim Brotherhood accused the Damascus regime of being behind a new massacre in the strife-torn country and said the world community, including Arab nations, also bear responsibility.

The Islamist group said more than 100 people, including women and children, had been massacred on Wednesday in the town of Al-Kubeir, in the central Hama region, and dozens more were killed earlier the same day in Al-Haffa, a town in the coastal region of Latakia.

Syrian rebels went on the offensive in and around Damascus on Wednesday, a watchdog said, as activists accused regime forces of committing a “massacre” in Hama’s countryside that left at least 47 people dead.

The Local Coordination Committees, the main activist group spurring protests on the ground, said regime forces killed at least 47 people in the town of Mazraat al-Qubair in Hama’s countryside.

U.N.-Arab League envoy Kofi Annan will on Thursday propose that the western powers, Russia and China form a new international group to press President Bashar al-Assad into political talks to end the deadly crisis, diplomats said.

Annan could even call for Iran and other key Middle East nations to be let into the so-called Contact Group when he makes the proposal to the U.N. Security Council, sources said.

U.S. Secretary of State Hillary Clinton said Wednesday she would reserve judgment on a Russian proposal for a global conference on Syria that would include Iran together with other powers.

"It's hard to imagine inviting a country (Iran) that is stage managing the Assad regime's assault on its people," she said at the end of a visit to Azerbaijan, referring to Syrian President Bashar al-Assad.

Bombs and shootings in Iraq killed three people, including two policemen, and wounded nine others on Wednesday, security and medical officials said.

In the former insurgent bastion of Fallujah, in Anbar province west of Baghdad, gunmen on a motorcycle killed a policeman when they opened fire on a checkpoint in the center of the city, police Colonel Adil Mukhlaf said.

Yemeni authorities began on Wednesday to dismantle the main protest camp against former president Ali Abdullah Saleh, who stepped down in February after a year-long uprising.

Five bulldozers cleared several tents from the main roads near the capital's Sanaa University without any resistance from the youth who have occupied the district since February 2011, an Agence France Presse correspondent reported.