Iran deems "unacceptable" the Egyptian army's toppling of the country's first freely elected president Mohammed Morsi, the foreign ministry said on Monday.

"The intervention of armed forces in political affairs is unacceptable and disturbing," ministry spokesman Abbas Araqchi told the Mehr news agency, when asked about the developments in Egypt.

Gaza's Islamist Hamas rulers on Monday condemned the "massacre" of dozens of people demonstrating against last week's military coup which ousted former Egyptian president Mohammed Morsi, calling for an end to the bloodshed.

"Hamas condemns the massacre of dozens of peaceful Egypt civilians today at dawn, expresses its profound pain and sadness over the victims, and calls for an end to the bloodshed among the Egyptian people," it said in a statement.

Saudi Arabia beheaded one of its citizens on Monday after he was convicted of murdering a fellow Saudi in the southwestern Mecca region, the interior ministry said.

Saleh bin Ali al-Shemmarani was executed for stabbing to death Ali bin Saeed al-Shemmarani after a dispute between the two, the ministry said in a statement carried by SPA state news agency.

Turkey's foreign minister on Monday denounced the killing of 35 activists in Egypt who demonstrated against last week's military coup that unseated president Mohammed Morsi.

"I strongly condemn the massacre during the morning prayers on behalf of the fundamental values of humanity that we have defended," Ahmet Davutoglu wrote in a message on Twitter.

Syrian troops advanced on Monday into the rebel-held Khaldiyeh district of central Homs, with shelling intensifying as forces battled for a 10th day in the area, activists and an NGO said.

State media, meanwhile, reported two car bombs hit a regime-held area in the city, while the Syrian Observatory for Human Rights reported five killed in one car bombing.

Two days of violence in Iraq killed 19 people, including six family members shot dead while returning from a wedding, police officers and doctors said on Monday.

In Madain, south of Baghdad, a bomb exploded near a football field inside a sports club on Monday, killing at least five people.

Gunmen shot dead a high-ranking Yemeni army officer Monday in the country's southeastern Hadramawt province as he was heading to work, a military official told Agence France Presse.

The unknown assailants opened fire on Colonel Ahmed al-Suhaili, commander of a military camp in Hadramawt's city of Seiyun, the official said on condition of anonymity.

Egypt's Salafist al-Nur party said on Monday that it had withdrawn from talks on the formation of a new government in response to the killing of protesters calling for ousted president Mohammed Morsi to be reinstated.

"We have decided to withdraw immediately from all negotiations in response to the massacre outside the Republican Guard" headquarters, al-Nur spokesman Nadder Bakkar said on Twitter.

Fiji has announced it will send a further 380 troops to join a U.N. peacekeeping force in the Golan Heights, lifting the Pacific nation's contribution to 562.

The move comes after several countries withdrew from the peacekeeping force due to escalating violence stemming from the Syrian conflict.

Egypt's interim leader Adly Mansour launched an investigation into violence in Cairo that killed 42 people on Monday during an Islamist demonstration calling for the army to restore Mohammed Morsi as president.

"The president of the republic forms a judicial commission to investigate the events at the Republican Guard" headquarters, state television reported.